Foldable spray boom comprising a locking device and agricultural machine equipped with such a boom

Abstract

Foldable spray boom comprising a locking device and agricultural machine equipped with such a boom The present invention relates to a foldable spray boom (6) comprising a central frame (7), articulated arms (10, 11) and at least one locking device (21), each locking device (21) making it possible to hold one of the articulated arms (10, 11) relative to the other (11, 10) and comprising a boom support (22), a bracket (23) and a lock (24). Each locking device (21) comprises an integrated opening element (25) for neutralizing the action of the lock (24). The invention also relates to an agricultural machine (1) equipped with such a spray boom (6). Figure to be published with the abstract: Fig. 1

Description

Title of the invention: Foldable spray boom comprising a locking device and agricultural machine equipped with such a boom

[0001] The present invention relates to the field of agricultural machinery, in particular agricultural apparatus or machines for spreading products and more particularly booms used on spraying apparatus. Such agricultural apparatus are provided with at least one boom intended to spread, as uniformly as possible, fertilizers or treatment products of the phytosanitary type on crops or on the ground.

[0002] The present invention relates more specifically to a foldable spray boom comprising a locking device. The invention also relates to an agricultural machine comprising such a spray boom.

[0003] Spreading equipment in agricultural fields, such as crop spraying machines, generally uses a spray boom. The spray boom is suspended above the crops in the field and includes, among other things, spray nozzles and product supply lines coupled to it. Due to the width of such a boom, it is designed to be foldable for transport in order to comply with road clearance. It thus comprises several articulated elements and is equipped with a folding system, such as actuators. Typically, the boom has a right side part and a left side part, each articulated on a central frame connected to the chassis. The side parts (left and right) are positioned along the tractor or tank depending on the type of sprayer. Each side part is further divided into several arms.During transport, the boom is kept folded by means of a locking device. The locking device prevents accidental unfolding of the sprayer during transport. The side parts are inserted from above into a boom holder when folded, so that the boom rests in the boom holder along the tank.

[0004] Such a boom support is not suitable when the spray nozzles extend under the boom structure. For this type of boom, locking is carried out by means of a locking support which pivots at the end of the closing of the side parts via a locking tube. This locking support is actuated once the boom is completely folded, it then pivots downwards and locks the individual arms against each other. The locking support envelops the individual arms from above and does not give vertical support to the boom. In order not to damage the boom support and / or the side parts of the ramp, this locking device must be actuated at the end of the closing of the side part, it therefore requires the use of sensors to know the end of travel. After receiving the end of travel signal, the locking tube is actuated and the locking support pivots. Such a solution is therefore expensive, complex and has the disadvantage of not providing vertical support for the ramp.

[0005] Document US7431221 discloses a locking device for a spray boom whose deployment is carried out in several stages. The outer arm equipped with a stirrup is locked onto the intermediate arm equipped with a boom support. When the outer arm is folded, the latter is automatically locked in the boom support. From the transport configuration, the left side part pivots backwards to open the inner arm and then the intermediate and outer arms pivot. By this pivoting, the spring-biased lock opens by means of a cable system to release the stirrup and allow the outer arm to open. The cable exerts a linear retraction force on the lock and thus releases the locking device during a preliminary stage of the unfolding of the boom. Such a cable system may wear and stretch and no longer control the opening of the lock.Furthermore, such a cable device is dependent on specific boom kinematics. Furthermore, the direction of action of the lock on the boom support is horizontal, which requires perfect alignment between the outer arm and the intermediate arm. Regular maintenance operations on the cable and adjustment of the articulation between the outer arm and the intermediate arm are required.

[0006] The present invention aims to overcome at least the main drawbacks mentioned above. Ideally, the invention should make it possible to provide an independent, reliable, simple and economical unlocking device.

[0007] To this end, an important characteristic of the invention consists in that each locking device comprises an integrated opening element to neutralize the action of the lock. Thanks to this important characteristic, the action necessary on the lock for unfolding the ramp is carried out directly, at the level of the locking device. The direct action is advantageously carried out in parallel with the command to open the ramp. This locking device is transposable to any ramp kinematics having at least two articulated arms.

[0008] The invention will be better understood from the following description, which relates to a preferred embodiment, given by way of non-limiting example, and explained with reference to the appended schematic drawings, in which:

[0009] [fig. 1] represents an agricultural machine of the sprayer type with a folding boom in a transport configuration,

[0010] [fig.2] represents a half-ramp with several arms, the outer arm of which is in opening up,

[0011] [fig.3] is a sectional view of the locking device in an unlocked position. rusty,

[0012] Fig. 4] is a sectional view of the locking device in a locked position,

[0013] [fig.5] illustrates the ramp support secured to the inner arm,

[0014] [fig.6] illustrates the stirrup attached to the outer arm.

[0015] The agricultural machine 1 illustrated in Figure 1 is a sprayer designed for applying liquid in the form of drops to a specific target. This machine is intended to spread on the ground or to distribute on the vegetation phytosanitary products which act on the plants or on the parasites. The spreading of liquid fertilizers on the crops is also possible. The sprayer comprises a longitudinal chassis 2 and a tank 3 intended to contain the treatment products. In this embodiment, the chassis 2 is provided with wheels 4 and a drawbar 5. It is a sprayer of the trailed type intended to be coupled to a tractor (not shown). The agricultural machine 1 can be moved in a forward direction A, preferably by the tractor.In the remainder of the description, the terms or concepts “front”, “rear”, “in front”, “behind” are defined in relation to the direction of advance A of the agricultural machine 1 and the terms or concepts “right” and “left” are defined by looking at the agricultural machine 1 from behind and in the direction of advance A.

[0016] The sprayer also comprises a spray boom 6 which supports nozzles (not shown) which are used to spread the product. The spray boom 6 is constituted by a central frame 7 and two lateral parts 8, 9 or two half-booms connected on either side of the central frame 7. One lateral part extends to the left and the other extends to the right of the central frame 7. The two lateral parts 8, 9 are advantageously symmetrical with respect to a median vertical plane of the chassis 2. To increase the efficiency of the sprayer during work, its boom can reach several tens of meters whereas for circulation on roads and paths, the sprayer must respect a reduced width. Thus the spray boom 6 is designed to be able to fold and each lateral part 8, 9 comprises several articulated arms 10, 11 which can fold several times along the tank 3 during transport.For this purpose, the ramp 6 is equipped with a manual operating system or one consisting of actuating elements for folding or deploying the articulated arms 10, 11.

[0017] Such an agricultural machine 1 has means for taking the product to be spread contained in the tank 3 and sending it under pressure to nozzles. The nozzles and the set of pipes (not shown) in which the product to be spread circulates are supported by the spraying boom 6. Advantageously, the boom 6 is secured to the chassis 2 by means of a central frame 7. More precisely, it is the central frame 7 of the boom 6 which is connected to the chassis 2. The connecting device 7 makes it possible to adjust the spraying height of the boom 6 relative to the ground by means of a height adjustment linkage.

[0018] Typically, in order to reduce the overall size of the agricultural machine 1, outside of working periods, the articulated arms 10, 11 are folded onto each other and are brought back along the machine. The lateral parts 8, 9 are made up of several arms 10, 11 connected to each other by means of articulations with a substantially vertical axis so that they can be folded into the transport position. In the embodiment shown, the spraying boom 6 comprises on each side an outer arm 10 and an inner arm 11. Each lateral part 8, 9 therefore comprises an inner arm 11 secured to the central frame 7 by means of an inner articulation 12 with an axis 12a. This inner articulation 12 is a combination of a lower connection 13 and an upper connection 14.The side parts 8, 9 can be folded and deployed around the respective axis 12a passing through the lower link 13 and the upper link 14 by means of a respective inner actuator 15. The inner actuator 15 is arranged between the central frame 7 and the inner arm 11 of the respective side part 8, 9. Advantageously, the upper link 14 comprises a tilting means, preferably in the form of an adjustable spacer, for adjusting the tilt of the side part 8, 9 of the spray boom 6 relative to the ground.

[0019] Figure 1 illustrates the sprayer in a transport configuration. In this figure the left lateral part 8 of the boom 6 is shown in a folded position. The two arms 10 and 11 of the left lateral part 8 extend along the tank 3. The inner arm 11 is folded against the tank 3 and the outer arm 10 is folded against the inner arm 11. The arms 10 and 11 extend substantially parallel to the median vertical plane of the chassis 2. The right lateral part 9 is, for its part, shown in an intermediate position since the outer arm 10 has not yet pivoted completely against the inner arm 11. The inner arm 11 is already in its transport position, it rests against a holding device 16. The holding device 16 comprises a relief configured to receive the inner arm 11. The relief provides support in the vertical direction of the half-boom.The complete pivoting of the inner arm 11 around the axis 12a of the inner joint 12 was carried out via the inner actuator 15. The intermediate position shown illustrates the outer arm 10 just before its complete folding or just after the start of its deployment. One can also speak of an initial opening phase or a final folding phase. The free end of the outer arm 10 moves away from or approaches the arm. interior 11 by pivoting around its articulation axis.

[0020] Figure 2 illustrates in more detail a part of spray boom 6. This is the right lateral part 9 and more precisely the outer arm 10 which is opening relative to the inner arm 11. This representation could also correspond to the closing or folding of the outer arm 10. The opening is more substantial than that shown in Figure 1. The outer arm 10 is secured to the inner arm 11 by means of an outer articulation 17 with axis 17a. This outer articulation 17 is composed of a lower junction 18 and an upper junction 19. The outer arm 10 can be deployed and folded around the axis 17a passing through the two junctions 18 and 19 by means of an outer actuator 20. The outer actuator 20 extends between the inner arm 11 and the outer arm 10 of the respective lateral part 8, 9.In the exemplary embodiment, the outer arm 10 is configured to allow a forward pivoting movement around the axis 17a. The axis 17a of the outer joint 17 is slightly inclined to counter the torsional deformation of the ramp during the opening or closing phases. Advantageously, the outer joint 17 is composed of the two joints 18, 19, each being a ball joint. According to an alternative not shown, the lower joint is a ball joint and the upper joint is a connecting rod or vice versa. According to another alternative, the outer joint 17 is composed of two pivot joints with a vertical axis.

[0021] The inner or outer actuators 15, 20 are actuating elements of the double-acting hydraulic cylinder type. In Figure 2, the outer actuator 20 is combined with a connecting rod type system to allow an opening of more than 130° of the outer arm 10 relative to the inner arm 11. The system may also be an association of a connecting rod with a counter connecting rod and / or a rack.

[0022] From the folded transport configuration, the inner and outer arms 11 and 10 are deployed using the respective actuators 15 and 20 to reach the working configuration. The boom is said to be deployed or open. In the working configuration not shown, the sprayer is moved over a field containing plants to be treated with the spray boom 6 which extends transversely to the direction of advance A and on either side of the median vertical plane of the chassis 2. The two lateral parts 8, 9 are advantageously symmetrical. The left and right lateral parts 8, 9 are aligned with the central frame 7. The outer arm 10 and the inner arm 11, of each lateral part 8, 9, extend in the extension of one another and are substantially aligned.

[0023] In the case of a very wide ramp, each side part 8, 9 can be subdivided into more than two articulated arms. It is common for each side part to be subdivided into three arms. Thus, an intermediate arm extends between the inner arm 11 and the outer arm 10. Each arm is articulated relative to each other and is capable of pivoting using a respective actuator. A ramp subdivided into four arms, therefore more than three arms, is also part of the invention.

[0024] The length of the boom 6 during transport, in the direction parallel to the chassis 2, is reduced since each lateral part comprises several articulated arms 10, 11 which fold onto each other thanks to the actuators 15, 20. The spray boom 6 extends to the rear of the chassis 2 and is configured to allow the lateral parts 8, 9 to be folded forward. The kinematics of the spray boom 6, shown in FIGS. 1 and 2, are such that during deployment, the outer arm 10 pivots forward and the inner arm 11 pivots rearward. The lateral parts 8, 9 move from an orientation parallel to the chassis 2 to an orientation perpendicular to the chassis 2. When the inner arm 11 is deployed, it extends in line with the central frame 7 and the outer arm 10 extends in alignment with the inner arm 11.

[0025] The structure of the boom 6, shown in the figures, consists of an assembly of elongated elements such as tubes. The assembly of elongated elements comprises an upper tube, two lower tubes and spacer elements which connect the tubes together. Generally, the nozzles are provided inside the boom structure, they are fixed between the lower tubes and extend between the spacer elements. Alternatively, the nozzles extend under the spray boom 6, that is to say under its structure so as to provide greater mounting flexibility with regard to the spacing between the nozzles. The nozzles are therefore arranged under the spacer elements. The relief of the holding device 16 is configured to receive the upper tube of the inner arm 11 in the transport configuration.To absorb shocks or oscillations during transport, the relief is covered or provided with rubber or similar. The relief can be achieved by a caster.

[0026] To prevent accidental deployment of the spray boom 6 in the transport configuration, the boom 6 is held in its folded or closed position by means of a locking device 21. This device allows each outer arm 10 to be held in position without any relative movement with the inner arm 11. For this purpose, the locking device 21 comprises a boom support 22 and a bracket 23. The boom support 22 is secured to the inner arm 11 and the bracket 23 is secured to the outer arm 10. The bracket 23 is configured and adapted to be housed in the boom support 22 in a folded position of the outer arm 10. In the final folding phase shown in FIG. 3, the bracket 23 moves by sliding and locks with the boom support 22 so as to hold the outer arm 10 relative to the inner arm 11. The locking device 21 is also provided with a lock 24. This is a spring lock or similar. This spring lock allows an automatic closing state. In the embodiment shown in Figure 4, the lock 24 is secured to the ramp support 22 and allows the bracket 23 to be secured in the ramp support 22.

[0027] The invention therefore particularly relates to a foldable spray boom 6 comprising a central frame 7, articulated arms 10, 11 and at least one locking device 21, each locking device 21 making it possible to hold one of the arms 10, 11 relative to the other 11, 10 and comprising a boom support 22, a stirrup 23 and a lock 24.

[0028] According to an important characteristic of the invention, each locking device 21 comprises an integrated opening element 25 to neutralize the action of the lock 24. Thanks to this opening element 25, the action necessary on the lock 24 to authorize the unfolding of the ramp 6 is carried out directly at the locking device 21. The action is localized and direct at the ramp support 22. Advantageously, the action for opening the lock 24 is carried out in parallel with the command to open the ramp 6 and in particular in parallel with the command of the external actuator 20. The command of the opening element 25 is independent of the position of the articulated arms 10, 11. This locking device 21 is transposable to any ramp kinematics having at least two articulated arms. It is not dependent on any particular kinematics and easily adapts to all folding ramps.

[0029] In a particularly advantageous manner, the opening element 25 is configured to act in a substantially vertical direction, when the spray boom 6 is in its transport configuration. With a vertical action, the locking is not sensitive to misalignment defects between the inner and outer arms 11 and 10.

[0030] Advantageously, the lock 24 is configured to provide a non-reversible positive locking system. That is to say, the lock 24 is capable of closing automatically and maintaining this state until its opening is commanded. Unlocking the device requires a specific action on the lock 24 while locking is done automatically when the ramp is folded. Thanks to the lock 24, the outer arm 10 is held in its folded position against the inner arm 11.

[0031] In the embodiment shown in more detail in Figures 5 and 6, the opening element 25 is produced by an actuator of the single-acting cylinder type. The opening element 25 is provided on the ramp support 22 and extends within the space occupied by the ramp support 22. The action of the opening element 25 is direct and advantageously takes place in parallel with the opening control of the ramp 6. This is a compact and maintenance-free locking solution.

[0032] As illustrated in Figures 5 and 6, the ramp support 22 comprises at least one housing 26 suitable and intended to receive at least one stop 27 provided on the stirrup 23. The stop 27 is capable of being covered with a material different from that of the housing 26 to avoid premature wear of the housing 26. The stop 27 is covered with a material other than steel, a material having a lower hardness. Preferably, the stop 27 is covered with a plastic material. The housing 26 and the stop 27 have a corresponding shape. The section of the housing 26 and the stop 27 is advantageously circular. The diameter of the stops 27, 29 is preferably identical but could be different. The ramp support 22 is made of two yokes provided with at least one housing 26, 28. The opening element 25 is integral with the ramp support 22 and is positioned between the two yokes.The dimensions of the opening element 25 are such that they fit within the dimensions of the ramp support 22. The ramp support 22 is further equipped, on its upper part, with surfaces for guiding the reception of the stop 27 in its housing 26. These surfaces advantageously form a guide V open towards the outside in the transport configuration.

[0033] In the locked position of the locking device as seen in Figure 4, the opening element 25 is suitable and intended to block or hold the stop 27 in its housing 26. According to a preferred embodiment, the ramp support 22 is provided with a housing 26 and a secondary housing 28, each suitable and intended to receive respectively the stop 27 and the secondary stop 29 provided on the stirrup 23. The stirrup 23 is composed of two vertical plates between which the stops 27, 29 are fixed. The use of a locking device 21 with two stops 27 and 29 makes it possible to keep the outer arm 10 locked in torsion. The stirrup 23 is secured to the outer arm 10 using fixing screws. Other fixing means, for example via rivets, welding or gluing, are also possible. The ramp support 22 is secured to the inner arm 11 with screws.Its position on the inner arm 11 is adjustable in height thanks to the vertical grooves to be able to position it relative to the stirrup 23. As visible in Figure 4, the stop 27 and the secondary stop 29 are positioned on the stirrup 23 in a slightly offset manner in height and laterally. The housings 26 and 28 are also offset in height and laterally relative to each other. The secondary housing 28 is positioned so that the opening element 25 extends between the two housings 26 and 28. The secondary stop 29 is arranged on the stirrup 23 in such a way that the opening element 25 extends and can be inserted between the two stops 27 and 29. Preferably, the end of the rod of the cylinder or of the opening element 25 is spherical. The diameter of the stops 27, 29 are substantially identical.

[0034] According to an advantageous embodiment of the invention, the opening element 25 is made by a single-acting cylinder. It is mounted in parallel with the hydraulic circuit for controlling one of the actuating elements for folding and / or deploying the ramp 6. Preferably, the opening element 25 is connected in parallel with the external actuator 20 of the corresponding lateral part. The rod-side chamber for opening the lock 24 is connected to the external actuator 20. The rod-side chamber of the opening element 25 is advantageously connected to the large chamber of the external actuator 20. Thus, when the opening or deployment of the ramp 6 is commanded, the locking device 21 is controlled automatically; there is no specific device to control or specific position to respect. When the ramp 6 closes, the opening element 25 is momentarily pushed downwards to free the passage from the stop 27 to the housing 26. The spherical shape of the end of the cylinder rod facilitates this downward pushing movement.It is the inertia of the ramp 6 when it is folded which makes it possible to overcome the force of the spring 30 and allow the locking of the outer arm 10. The force exerted by the return spring 30 being stronger than the return pressure of the cylinder, the cylinder rod is pushed upwards.

[0035] In the example shown in Figure 2, the ramp support 22 is fixed to the upper tube of the ramp structure of the inner arm 11 and the stirrup 23 is fixed to the lower tube of the ramp structure of the outer arm 10, more precisely the lower tube closest to the upper tube of the inner arm 11 in the folded position.

[0036] It goes without saying that the present invention also relates to mounted sprayers as well as self-propelled sprayers. This spray boom 6 can be mounted at the front or rear of an agricultural tractor, or in another configuration the boom 6 can be integrated into a specific self-propelled machine.

[0037] Of course, the invention is not limited to the embodiment described and shown in the attached drawings. Modifications remain possible, in particular from the point of view of the constitution of the various elements or by substitution of technical equivalents, without departing from the scope of protection of the invention.

Claims

Claims

1. Foldable spray boom (6) comprising a central frame (7), articulated arms (10, 11) and at least one locking device (21), each locking device (21) making it possible to hold one of the articulated arms (10, 11) relative to the other (11, 10) and comprising a boom support (22), a bracket (23) and a lock (24) characterized in that each locking device (21) comprises an integrated opening element (25) to neutralize the action of the lock (24).

2. Spray bar according to claim 1, characterized in that the opening element (25) is configured to act in a vertical direction.

3. Spray bar according to claim 1 or 2, characterized in that the opening element (25) is provided on the bar support (22) and extends within the space occupied by the bar support (22).

4. Spray bar according to any one of claims 1 to 3, characterized in that the bar support (22) is provided with at least one housing (26) suitable and intended to receive at least one stop (27), covered with a material different from that of the housing (26), provided on the stirrup (23).

5. Spray bar according to claim 4, characterized in that the opening element (25) is suitable and intended to block the stop (27) in the housing (26).

6. Spray bar according to any one of claims 1 to 5, characterized in that the opening element (25) is produced by an actuator of the single-acting cylinder type.

7. Spray bar according to claim 6, characterized in that the rod-side chamber of the opening element 25 is connected to an external actuator 20 arranged between the outer arm 10 and the inner arm 11.

8. Spray bar according to claim 4, characterized in that the bar support (22) is provided with a housing (26) and a secondary housing (28), each of which is suitable and intended to receive respectively the stop (27) and a secondary stop (29) provided on the bracket (23).

9. Spray bar according to claim 8, characterized in that the secondary housing (28) is positioned so that the opening means (25) extends between the two housings (26, 28).

10. Agricultural machine comprising a spraying boom according to one of any of claims 1 to 9.

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