BE1028952B1 - Attachment coupling system for agricultural vehicles - Google Patents

Abstract

The invention relates to an agricultural vehicle (A) equipped with a coupling system for mechanically and hydraulically coupling an accessory (B) to said agricultural vehicle. More specifically, the coupling system comprises two cylinders (2, 4) and a hydraulic circuit (20, 30) making it possible to reduce the hydraulic pressure in the main circuits (10) during the decoupling of the accessory.

Description

System for coupling accessories for agricultural vehicles Field of the invention The invention relates to the field of agricultural vehicles.

More particularly, the invention relates to a coupling system for connecting an accessory to an agricultural vehicle.

State of the art

Agricultural vehicles can be equipped with one or more agricultural attachments that are designed to perform a variety of jobs.

Thus, depending on the agricultural accessory coupled to the agricultural vehicle, the agricultural vehicle is used to sow, spread, harvest, harvest, mulch or any other action performed by the agricultural vehicle by means of the agricultural accessory.

The connection between the agricultural vehicle and the agricultural implement involves the presence of both a mechanical and a hydraulic coupling system.

This coupling system allows the agricultural attachment to operate correctly on the agricultural vehicle, for example to control the agricultural attachment from the agricultural vehicle.

When coupling, it is necessary to be able to connect the hydraulic circuits of the attachment and the agricultural vehicle.

It is then necessary to decompress the circuits, in order to be able to effectively or more easily connect them.

Indeed, without decompression, it is necessary to fight against the pressure in the two circuits to be able to connect them, making the maneuver difficult, if not impossible.

Current technologies provide for a manual decompression system, obliging the operator to stop the engine of the agricultural vehicle in order to manually disconnect the pipes to ensure this decompression.

This has the effect of a loss of the working fluid which can represent a significant part.

When uncoupling, due to the pressure of the working fluid in the hydraulic circuits of the attachment and the agricultural vehicle, a loss of working fluid may again occur. Indeed, the pressurized working fluid is partially evacuated from the circuit at the time of decoupling.

Document FR 2 745 358 discloses a coupling assembly for mobile units, such as an agricultural vehicle and an agricultural accessory. However, this coupling assembly, although making it possible to reduce the pressure, is complex in its implementation.

Summary of the invention An object of the invention is to provide a mechanical and hydraulic coupling system between an agricultural vehicle and an agricultural implement which is simpler to handle and which reduces losses of working fluid.

The invention is defined by the independent claims. The dependent claims define preferred embodiments of the invention.

According to the invention, an agricultural vehicle is provided comprising a system for mechanical and hydraulic coupling of the vehicle to an agricultural accessory. This coupling system comprises a first double-acting hydraulic cylinder whose piston rod or cylinder is extended by a first lock capable of cooperating with the accessory to mechanically lock the accessory to the vehicle when the first cylinder is actuated in one direction and to mechanically unlock the accessory of the vehicle when the first cylinder is actuated in an opposite direction, and the cylinder of which is mechanically connected to the vehicle. The coupling system also comprises a second single- or double-acting hydraulic cylinder, the piston rod of which is mechanically connected to the piston rod of the first cylinder, and the cylinder of which is mechanically connected to the vehicle. The coupling system further comprises a hydraulic pump, as well as a first pair of hydraulic connectors arranged to cooperate with a second pair of hydraulic connectors of the accessory when the accessory is coupled to the vehicle. The coupling system also comprises a first hydraulic circuit connecting the hydraulic pump to the first pair of hydraulic connectors and configured to transmit hydraulic pressure to the accessory, a second hydraulic circuit connecting the hydraulic pump to the first hydraulic cylinder and configured to actuate the first hydraulic cylinder in one direction or in the opposite direction, and a third hydraulic circuit connecting the first hydraulic circuit to the cylinder chamber of the second hydraulic cylinder located on the side of the piston rod of the second hydraulic cylinder. This third hydraulic circuit comprises two first non-return valves configured to only allow passage of hydraulic fluid from the first hydraulic circuit to said chamber of the cylinder of the second hydraulic cylinder located on the side of the piston rod of the second hydraulic cylinder. Finally, a second non-return valve connected between the second hydraulic circuit and the third hydraulic circuit is configured to only allow passage of hydraulic fluid from the third hydraulic circuit to the second hydraulic circuit. This configuration with hydraulic cylinders allows a simple and efficient connection between the agricultural vehicle and the attachment. The first hydraulic circuit allows the attachment to be controlled from the agricultural vehicle. The second hydraulic circuit makes it possible to control the first hydraulic cylinder, which activates the mechanical coupling of the accessory to the agricultural vehicle, or its decoupling when it acts in the opposite direction. The third hydraulic circuit, comprising two first non-return valves, makes it possible, by means of the second hydraulic cylinder connected as described to the first hydraulic cylinder, to decompress the hydraulic circuits of the accessory and of the agricultural vehicle during decoupling, this which reduces the losses of working fluid during coupling and/or during decoupling. The presence of the second non-return valve prevents the circulation of working fluid from the second circuit to the third circuit.

According to a first preferred embodiment, the cylinders of the first and of the second hydraulic cylinder are fixedly connected to the agricultural vehicle.

According to a second preferred embodiment, the cylinders of the first and of the second hydraulic jack are connected so as to be able to move in translation to the agricultural vehicle, the direction of said translation being parallel to the axis of the first hydraulic jack, and the cylinder of the first hydraulic jack is extended by a second lock able to cooperate with the accessory to mechanically lock the accessory to the vehicle when the first jack is actuated in one direction and to mechanically unlock the accessory from the vehicle when the first jack is actuated in one direction. opposite. Indeed, the presence of the second lock makes it possible to solidify the coupling.

According to this second preferred embodiment, the agricultural vehicle preferably comprises a first stop limiting the translational movement of the piston of the first hydraulic cylinder. In this same alternative, the agricultural vehicle preferably also comprises a second stop limiting the movement in translation of the cylinder of the first hydraulic cylinder.

According to this second preferred embodiment, the agricultural vehicle according to the invention is characterized in that the axis of the second hydraulic cylinder is parallel to the axis of the first hydraulic cylinder. This arrangement further simplifies the implementation of the coupling system.

According to this second preferred embodiment, the agricultural vehicle according to the invention is preferably characterized in that the diameter of the piston of the first hydraulic jack is preferably between 25 and 35 mm and/or in that the diameter of the piston of the second hydraulic cylinder is preferably between 15 mm and 25 mm.

According to this second preferred embodiment, the agricultural vehicle according to the invention is preferably characterized in that the nominal working pressure of the first hydraulic cylinder has a value preferably between 100 bar and 200 bar and/or in that the nominal working pressure of the second hydraulic cylinder has a value preferably between 1 bar and 20 bar.

According to a third preferred embodiment, the cylinders of the first and of the second hydraulic cylinder are connected so as to move in translation to the agricultural vehicle, the direction of said translation being parallel to the axis of the first hydraulic cylinder, the piston rod of the first hydraulic cylinder is common to or in the extension of the piston rod of the second hydraulic cylinder, and the cylinder of the second hydraulic cylinder is extended by a second lock capable of cooperating with the accessory to mechanically lock the accessory to the vehicle when the first ram is actuated in one direction and to mechanically unlock the vehicle accessory when the first ram is actuated in an opposite direction.

According to this third preferred embodiment, the piston rod of the first hydraulic cylinder is preferably common to the piston rod of the second hydraulic cylinder. According to this third preferred embodiment, the piston of the first hydraulic cylinder has preferably the same diameter as the piston of the second hydraulic cylinder.

According to this third preferred embodiment, the cylinder of the first hydraulic jack preferably has the same diameter as the cylinder of the second hydraulic jack.

Brief Description of the Figures These and other aspects of the invention will be clarified in the detailed description of particular embodiments of the invention, reference being made to the drawings of the figures, in which: Fig.1 shows a coupling system according to a first embodiment of the invention; Fig.2 shows a coupling system according to a second embodiment of the invention; Fig.3 shows a coupling system according to the first embodiment according to the invention, when the pump supplies the first hydraulic circuit; Fig.4 shows a coupling system according to the first embodiment according to the invention, when the pump supplies the first hydraulic circuit;

Fig.5 shows a coupling system according to the first embodiment according to the invention, when the pump supplies the second hydraulic circuit, when the accessory is unlocked; Fig.6 shows a coupling system according to the first embodiment according to the invention, when the pump supplies the second hydraulic circuit, when locking the accessory; Fig.7 shows a coupling system according to a third embodiment of the invention.

Figure drawings are not to scale or proportionate. Generally, similar or identical elements are denoted by identical references in the figures.

Detailed description of embodiments of the invention Fig.1 illustrates, according to a first embodiment, the agricultural vehicle (A) according to the invention, comprising a mechanical and hydraulic coupling system (1) of the vehicle ( A) to an agricultural implement (B). The hydraulic connection takes place at the level of the pair of connectors (6a) of the agricultural vehicle (A) and the pair of connectors (6b) of the accessory (B).

The coupling system (1) comprises a first double-acting hydraulic cylinder (2). A double-acting cylinder has two working directions. It has two feed ports and pressure can be applied to either side of the piston allowing it to move in either direction. The piston rod (2a) of this first hydraulic cylinder (2) is extended by a first lock (3a) capable of cooperating with the accessory (B) to mechanically lock the accessory (B) to the vehicle (A) when the first jack (2) is actuated in one direction and to mechanically unlock the accessory (B) of the vehicle (A) when the first jack (2) is actuated in an opposite direction. The first lock (3a) can for example be a simple rod that can be inserted into a corresponding hole in the accessory (B).

The coupling system (1) also includes a second hydraulic cylinder (4), which can be single or double acting. In the figures, the second hydraulic jack is single-acting, but those skilled in the art can easily replace it with a double-acting hydraulic jack. The piston rod (4a) of the second hydraulic cylinder (4) is mechanically connected to the piston rod (2a) of the first hydraulic cylinder (2). The piston rod (4a) of the second hydraulic cylinder (4) is thus made mechanically integral with the piston rod (2a) of the first hydraulic cylinder (2), so that when the piston of the first hydraulic cylinder ( 2) is moved, this causes the same movement of the piston of the second hydraulic cylinder (4).

In this first embodiment, the cylinders (2b, 4b) of the first (2) and second (4) hydraulic cylinders are integral with each other. This means that the cylinders (2b, 4b) are interconnected in such a way that there can be no relative movement of one cylinder with respect to the other. The cylinders (2b, 4b) of the first (2) and second (4) hydraulic cylinders can for example be directly connected to each other, such as for example via a piece welded or screwed onto their respective cylinders or by welding directly their two cylinders together.

The cylinders (2b, 4b) of the first (2) and second (4) hydraulic cylinders are also connected to the vehicle (A), either in a fixed manner or in a mobile manner. Preferably, the axis of the second hydraulic cylinder (4) is parallel to the axis of the first hydraulic cylinder (2).

The coupling system (1) also comprises a hydraulic pump (5). It can be fitted with a tank (not shown) to compensate for any small losses of working fluid. This pump (5) is able to operate both in suction and in injection of fluid. The pump (5) can therefore be reversed. Or it may be a pump (5) which only works in one direction, with a circuit inversion system placed after the pump (5), allowing the direction of circulation of the fluid to be modified. work.

The coupling system (1) comprises a first hydraulic circuit (10). It connects the hydraulic pump (5) to the first pair of hydraulic connectors (6a). It is configured to transmit hydraulic pressure to the attachment (B) in order to control it from the agricultural vehicle (A). As indicated by the arrows in Fig.3 and 4, the direction of circulation of the working fluid in this first hydraulic circuit (10) can be in one or the other direction. This first hydraulic circuit (10) can also be multiplied according to the possibilities of controlling the accessory (B) or even the number of accessories connected to the agricultural vehicle (A).

The coupling system (1) comprises a second hydraulic circuit (20). This circuit (20) connects the hydraulic pump (5) to the first hydraulic cylinder (2). In the figures, it is the same pump (5) which supplies the first (10) and second (20) hydraulic circuits. The supply by the pump (5) of one or the other of the first (10) and second (20) hydraulic circuits is carried out by means of a circuit selector (8) as illustrated for example. Other configurations are possible: a second hydraulic circuit (20) completely independent of the first hydraulic circuit (10) but also connected to the same pump (5), a second hydraulic circuit (20) completely independent of the first hydraulic circuit (10) connected to a second pump (5), etc … . This second hydraulic circuit (20) is configured to actuate the first hydraulic cylinder (2) in one direction or in the opposite direction, depending on the direction of circulation of the working fluid in this second hydraulic circuit (20).

The coupling system (1) comprises a third hydraulic circuit (30). It connects the first hydraulic circuit (10) to the cylinder chamber (4b) of the second hydraulic cylinder (4) located on the side of the piston rod (4a) of the second hydraulic cylinder (4). This third hydraulic circuit (30) comprises two first non-return valves (7a) configured to only allow passage of hydraulic fluid from the first hydraulic circuit (10) to the cylinder chamber (4b) of the second hydraulic cylinder (4) located on the side of the piston rod (4a) of the second hydraulic cylinder (4).

The coupling system (1) comprises a second non-return valve (7b) connected between the second hydraulic circuit (20) and the third hydraulic circuit (30). This second non-return valve (7b) is configured to only allow hydraulic fluid to pass from the third hydraulic circuit (30) to the second hydraulic circuit (20). The pump (5) is configured to suck and inject the working fluid into the hydraulic circuits (10, 20, 30).

Fig.2 illustrates a second embodiment of an agricultural vehicle (A) according to the invention. According to this second embodiment, the agricultural vehicle (A) is identical to that described in Fig.1, except that here the cylinders (2b, 4b) of the first (2) and of the second (4) hydraulic cylinders are connected together and movably in translation to the agricultural vehicle (A). For this purpose, one can for example provide a groove in a connecting piece between the two cylinders, the groove extending in a direction parallel to the axis of the first hydraulic cylinder (2), and a rod connected to the vehicle and s inserting into said groove. This translation is carried out parallel to the axis of the first hydraulic cylinder (2). Preferably, the agricultural vehicle comprises in this case a first stop (9a) limiting the movement in translation of the piston of the first (2) and of the second (4) hydraulic cylinder. Preferably, the agricultural vehicle comprises in this case a second stop (9b) limiting the displacement in translation of the cylinder (2b, 4b) of the first (2) and of the second (4) hydraulic cylinder. In the groove example above, one end of the groove can act as either the first stopper or the second stopper. In this second embodiment, the cylinder (2b) of the first hydraulic cylinder (2) is preferably extended by a second lock (3b), able to cooperate with [accessory to mechanically lock the accessory (B) to the vehicle (A) when the first jack (2) is actuated in one direction and to mechanically unlock the accessory (B) from the vehicle (A) when the first jack (2) is actuated in the opposite direction.

As indicated above, Fig.3 and 4 illustrate the circulation of the working fluid in the first hydraulic circuit (10) depending on whether the pump (5) is activated in one direction or the other, for the first embodiment.

The non-return valves (7a) do not prevent the circulation of the working fluid from the first hydraulic circuit (10) to the second hydraulic circuit (20). However, the working fluid pressure in the second (20) and third (30) hydraulic circuits and the fact that these circuits are closed (no evacuation of the working fluid possible), has the consequence that the work does not use the communication between the first hydraulic circuit (10) and the second hydraulic circuit (20). Fig.5 illustrates the circulation of the working fluid during the decoupling of the accessory (B), for the first embodiment.

The pump (5) injects the working fluid as indicated by the direction of the arrows.

The working fluid is thus injected into the chamber on the side of the piston rod (2a) of the first hydraulic cylinder (2). This rod causes the first lock (3a) to unlock the accessory (B) of the agricultural vehicle (A). The thrust of the piston of the first hydraulic cylinder (2) ejects working fluid from the chamber located on the other side of the piston rod (2a) of the first hydraulic cylinder, which is returned to the pump (5). At the same time, the piston rod (4a) of the second hydraulic cylinder (4), integral with the piston rod (2a) of the first hydraulic cylinder (2), is actuated.

There is therefore a call for hydraulic fluid in the chamber on the side of the piston rod (4a) of the second hydraulic cylinder (4). This working fluid cannot come from the communication between the second (20) and the third (30) hydraulic circuits due to the presence of the second non-return valve (7b). This fluid is therefore drawn from the accessory (B) via the connection between the first (10) and the second (20) hydraulic circuits.

This has the effect of minimizing the losses of working fluid during the uncoupling of the accessory (B) from the agricultural vehicle (A). Fig.6 illustrates the circulation of the working fluid during the coupling of the accessory (B), for the first embodiment.

The pump (5) injects the working fluid as indicated by the direction of the arrows. The working fluid is thus injected into the chamber on the side opposite the piston rod (2a) of the first hydraulic cylinder (2). This rod causes the first lock (3a) to lock the accessory of the agricultural vehicle. The thrust of the piston of the first hydraulic cylinder (2) ejects working fluid from the chamber located on the side of the piston rod (2a) of the first hydraulic cylinder, which is returned to the pump (5). At the same time, the piston rod (4a) of the second hydraulic cylinder (4), integral with the piston rod (2a) of the first hydraulic cylinder (2), is actuated. There is therefore a discharge of hydraulic fluid in the chamber on the side of the piston rod (4a) of the second hydraulic cylinder (4). This working fluid cannot be evacuated via the communication between the first (10) and the third (30) hydraulic circuits due to the presence of the first non-return valves (7a). This fluid is therefore ejected towards the first hydraulic circuit (10), the second non-return valve (7b) not preventing the circulation in this direction. This has the effect of reducing the pressure of the working fluid in the first hydraulic circuit (10), thus allowing the coupling of the accessory (B) to the agricultural vehicle (A).

Preferably, the agricultural vehicle (A) is characterized in that the diameter of the piston of the first hydraulic cylinder (2) is between 25 mm and 35 mm.

Preferably, the agricultural vehicle (A) is characterized in that the diameter of the piston of the second hydraulic jack (4) is between 15 mm and 25 mm.

Preferably, the agricultural vehicle (A) is characterized in that the nominal working pressure of the first hydraulic jack (2) has a value between 100 bar and 200 bar.

Preferably, the agricultural vehicle (A) is characterized in that the nominal working pressure of the second hydraulic cylinder (4) has a value between 1 bar and 20 bar.

The mode of operation is analogous in the second embodiment as illustrated in FIG. 2, except that in this case the second lock (3b) will act in addition to the first lock (3a).

Fig.7 shows a coupling system according to the third embodiment of the invention. In this third embodiment, the cylinders (2b, 4b) of the first (2) and of the second (4) hydraulic cylinder are connected so as to be able to move in translation to the agricultural vehicle (A), the direction of said translation being parallel to the axis of the first hydraulic cylinder (2), and the piston rod (2a) of the first hydraulic cylinder (2) is common to or is in the extension of the piston rod (4a) of the second hydraulic cylinder (4) . The cylinder (4b) of the second hydraulic cylinder (4) is also extended by a second lock (3b) capable of cooperating with the accessory (B) to mechanically lock the accessory (B) to the vehicle (A) when the first actuator (2) is actuated in one direction and to mechanically unlock the accessory (B) of the vehicle (A) when the first actuator (2) is actuated in an opposite direction.

As illustrated in Fig.7, the hydraulic circuits are for the rest identical or similar to those of the first and second embodiment, so that the mode of operation is similar to that of the first and/or second mode of achievement.

According to this third embodiment, and as illustrated in Fig.7, the piston rod (2a) of the first hydraulic cylinder (2) is preferably common to the piston rod (4a) of the second hydraulic cylinder (4 ).

According to this third embodiment, the piston of the first hydraulic jack (2) preferably has the same diameter as the piston of the second hydraulic jack (4).

According to this third embodiment, the cylinder (2b) of the first hydraulic jack (2) preferably has the same diameter as the cylinder (4b) of the second hydraulic jack (4).

The present invention has been described in relation to specific embodiments, which are purely illustrative and should not be construed as limiting. In general, it will appear obvious to those skilled in the art that the present invention is not limited to the examples illustrated and/or described above. The presence of reference numbers in the drawings cannot be considered as limiting, including when these numbers are indicated in the claims.

The use of the verbs "understand", "include", "compose", or any other variant, as well as their conjugations, can in no way exclude the presence of elements other than those mentioned. The use of the indefinite article "un", "une", or of the definite article "le", "la" or "l'", to introduce an element does not exclude the presence of a plurality of these elements. The invention can also be described as follows: an agricultural vehicle (A) equipped with a coupling system for mechanically and hydraulically coupling an accessory (B) to said agricultural vehicle. The coupling system comprises in particular two jacks (2, 4) and hydraulic circuits (20, 30) making it possible to reduce the hydraulic pressure in the main hydraulic circuits (10) during the decoupling of the accessory.

Claims (14)

Claims 1. Agricultural vehicle (A) comprising a mechanical and hydraulic coupling system (1) of the vehicle (A) to an agricultural accessory (B), said coupling system (1) comprising: - a first hydraulic cylinder (2) with double effect of which the piston rod (2a) or the cylinder (2b) is extended by a first lock (3a) capable of cooperating with the accessory (B) to mechanically lock the accessory (B) to the vehicle (A) when the first jack (2) is actuated in one direction and for mechanically unlocking the accessory (B) of the vehicle (A) when the first jack (2) is actuated in an opposite direction, and whose cylinder (2b) is connected mechanically to the vehicle (A); - a second single- or double-acting hydraulic cylinder (4), whose piston rod (4a) is mechanically connected to the piston rod (2a) of the first cylinder (2), and whose cylinder (4b) is mechanically connected to the vehicle (A); - a hydraulic pump (5); - a first pair of hydraulic connectors (6a) arranged to cooperate with a second pair of hydraulic connectors (6b) of the accessory (B) when the accessory (B) is coupled to the vehicle (A); - a first hydraulic circuit (10) connecting the hydraulic pump (5) to the first pair of hydraulic connectors (Ga) and configured to transmit hydraulic pressure to the accessory (B); - a second hydraulic circuit (20) connecting the hydraulic pump (5) to the first hydraulic cylinder (2) and configured to actuate the first hydraulic cylinder (2) in one direction or in the opposite direction; - a third hydraulic circuit (30) connecting the first hydraulic circuit (10) to the cylinder chamber (4b) of the second hydraulic cylinder (4) located on the side of the piston rod (4a) of the second hydraulic cylinder (4) , said third hydraulic circuit (30) comprising two first non-return valves (7a) configured to only allow passage of hydraulic fluid from the first hydraulic circuit (10) to said cylinder chamber (4b) of the second hydraulic cylinder (4 ) located on the side of the piston rod (4a) of the second hydraulic cylinder (4); - a second non-return valve (7b) connected between the second hydraulic circuit (20) and the third hydraulic circuit (30) and configured to only allow passage of hydraulic fluid from the third hydraulic circuit (30) to the second circuit hydraulic (20). 2. Agricultural vehicle (A) according to claim 1, characterized in that the cylinders (2b, 4b) of the first (2) and of the second (4) hydraulic cylinder are fixedly connected to the agricultural vehicle (A). 3. Agricultural vehicle (A) according to claim 1, characterized in that the cylinders (2b, 4b) of the first (2) and of the second (4) hydraulic cylinder are re- connected movably in translation to the agricultural vehicle (A ), in that the direction of said translation is parallel to the axis of the first hydraulic cylinder (2), and in that the cylinder (2b) of the first hydraulic cylinder (2) is extended by a second lock (3b ) adapted to cooperate with the accessory (B) to mechanically lock the accessory (B) to the vehicle (A) when the first cylinder (2) is actuated in one direction and to mechanically unlock the accessory (B) from the vehicle (A) when the first cylinder (2) is actuated in the opposite direction. 4. Agricultural vehicle (A) according to claim 3, characterized in that the vehicle (A) comprises a first stop (9a) limiting the movement in translation of the piston of the first hydraulic jack (2). 5. Agricultural vehicle (A) according to claim 3 or 4, characterized in that the vehicle (A) comprises a second stop (9b) limiting the translational movement of the cylinder (2b) of the first hydraulic cylinder (2). 6. Agricultural vehicle (A) according to any one of the preceding claims, characterized in that the axis of the second hydraulic cylinder (4) is parallel to the axis of the first hydraulic cylinder (2). 7. Agricultural vehicle (A) according to any one of the preceding claims, characterized in that the diameter of the piston of the first hydraulic cylinder (2) is between 25 mm and 35 mm. 8. Agricultural vehicle (A) according to any one of the preceding claims, characterized in that the diameter of the piston of the second hydraulic cylinder (4) is between 15 mm and 25 mm. 9. Agricultural vehicle (A) according to any one of the preceding claims, characterized in that the nominal working pressure of the first hydraulic cylinder (2) has a value between 100 bar and 200 bar. 10. Agricultural vehicle (A) according to any one of the preceding claims, characterized in that the nominal working pressure of the second hydraulic cylinder (4) has a value between 1 bar and 20 bar. 11. Agricultural vehicle (A) according to claim 1, characterized in that the cylinders (2b, 4b) of the first (2) and of the second (4) hydraulic cylinder are connected so as to be able to move in translation to the agricultural vehicle (A). ), in that the direction of said translation is parallel to the axis of the first hydraulic cylinder (2), in that the piston rod (2a) of the first hydraulic cylinder (2) is common to or is in the extension of the piston rod (4a) of the second hydraulic jack (4), in that the cylinder (4b) of the second hydraulic jack (4) is extended by a second lock (3b) capable of cooperating with the accessory (B) to mechanically lock the accessory (B) to the vehicle (A) when the first cylinder (2) is actuated in one direction and to mechanically unlock the accessory (B) from the vehicle (A) when the first cylinder (2 ) is actuated in the opposite direction. 12. Agricultural vehicle (A) according to claim 11, characterized in that the piston rod (2a) of the first hydraulic cylinder (2) is common to the piston rod (4a) of the second hydraulic cylinder (4), 13. Agricultural vehicle (A) according to claim 12, characterized in that the piston of the first hydraulic cylinder (2) has the same diameter as the piston of the second hydraulic cylinder (4). 14. Agricultural vehicle (A) according to claim 12 or 13, characterized in that the cylinder of the first hydraulic jack (2) has the same diameter as the cylinder of the second hydraulic jack (4).