Seed drill

Abstract

Agricultural machine comprising a device for adjusting the position of an attachment (32) relative to a base (12), the adjustment device comprising a set of shims having one or more shims (621, 622) interposed between the attachment and the base in a first arrangement so as to fix a first position of the attachment on the base, the shim(s) being shaped so as to be positionable in a second arrangement so as to fix a second position of the attachment on the base, different from the first position. Figure for the abbreviation: Fig. 9

Description

Title of the invention: Seed drill technical field

[0001] The present invention relates to a seed drill intended to be mounted on agricultural machinery. Such a seed drill is intended to distribute a compound, in particular a seed or fertilizer, in the soil. The invention also relates to a sowing method using such a seed drill. Previous art

[0002] From application FR 3 070 233, a seed drill comprising a seed drill chute opening into a slot formed in the ground by an opening disc is known.

[0003] However, with such a seeder, vegetation can accumulate in front of the seeder chute and hinder the deposition of seeds.

[0004] Furthermore, this seeder includes a closing wheel allowing the slot in which the seeds have been deposited to be filled.

[0005] However, the filling is not always satisfactory, particularly in the deepest part of the slit. As a result, birds may eat some of the seeds. Germination is also slowed.

[0006] There is a need for a new seed drill that will solve, at least partially, the aforementioned problems.

[0007] To meet this need, the applicant invented a seed drill which was the subject of patent application FR1905498, filed on May 25, 2019.

[0008] In continuing his research, the applicant then attempted to improve the efficiency of the pinch roller and the adaptability of the seeder to different terrain configurations.

[0009] The object of this patent application is to protect these improvements. Summary of the invention

[0010] The invention proposes a seed drill comprising a support intended, in a service position, to be towed by an agricultural machine in a direction of travel, the seed drill comprising: - an opening disc mounted to rotate on the support so as to create a slot in the ground, or "main slot"; - a seeding device rigidly fixed to the support and configured to, in the service position, extend at least partially into said main slot to deposit a compound.

[0011] According to a first main embodiment, the seeder further comprises a pinch roller mounted for rotation on the support around an X axis in such a way to roll on the ground in front of the seeding device, the longitudinal distance, along the direction of advancement, between the support area of ​​the pinch roller on the ground and the seeding device being less than 10 cm.

[0012] As will be seen in more detail later in the description, the pinch roller, in its operating position, is designed to pinch plants against the ground. Once held in place, the plants are released by the seeding device, which pushes them and rotates them around the pinch point. The risk of plants accumulating against the seeding device is therefore considerably reduced.

[0013] A seed drill according to the first principal embodiment of the invention may also include one or more of the following optional features: - the longitudinal distance, along the direction of advancement, between the support area of ​​the pinch roller on the ground and the seeding device is less than 20 cm, 10 cm, 5 cm, preferably less than 3 cm and / or greater than 0.5 cm; - the transverse distance, along a transverse direction, between the support area of ​​the pinch roller on the ground and the plane of the opening disc is less than 30 cm, preferably less than 10 cm, preferably less than 5 cm and / or greater than 0.5 cm, preferably greater than 1 cm; - the transverse distance between the support area of ​​the pinch roller on the ground and the plane of the opening disc is less than 30 mm; - the pinch roller is mounted to rotate on a pivot with axis X, the axis X extending in a transverse plane; - the X axis forms, with a horizontal plane, an angle greater than 5°, preferably greater than 7°, and / or less than 30°, preferably less than 15°; - the seeder includes a support arm, fixed to the support and carrying said pivot; - the lower end of the support arm is, according to the direction of advancement, in front of the upper end of the support arm; - the seeder includes an elastic push element for the pinch roller towards the ground, the elastic push element being preferably interposed between the support arm and the support.

[0014] According to a second main embodiment, the seeder also includes a tool for filling the main slot formed by the opening disc, the filling tool being rigidly fixed on the support and, in the service position, in sliding contact with the ground.

[0015] As will be seen in more detail in the rest of the description, unlike a static contact obtained with a conventional closing wheel, a sliding contact has proven particularly effective in filling the main slot without forming A cavity forms inside this slit. This ensures that the seed, once planted in the soil, is properly buried, facilitating germination.

[0016] A seed drill according to the second main embodiment of the invention may also include one or more of the following optional features: - the transverse distance between the seeding device and the filling tool is less than 30 mm, 20 mm, preferably less than 10 mm; - the lower opening of the main seed drill descent is in front of the filling tool; - the filling tool is a cracking tool arranged to create a secondary crack parallel to the main crack, preferably a secondary coulter or a secondary opening disc; - the transverse distance between the main coulter and the cracking tool is greater than 1 mm and / or less than 100 mm, preferably less than 30 mm, preferably less than 20 mm; - the cracking tool is configured to create a secondary crack whose volume is greater than 0.5 times the volume of the main crack and / or whose depth is greater than 0.5 times the depth of the main crack; - the cracking tool is a secondary coulter with a tapered leading edge, preferably made of tungsten carbide; - the secondary coulter has a thickness of less than 60 mm, preferably less than 30 mm, preferably less than 15 mm; - the seeder includes a secondary seed drill chute configured for depositing a compound in the secondary slot, preferably for depositing a fertilizer, preferably in the form of granules; - the seeder includes a scraper configured to rub against the ground in the operating position so as to push soil into the main furrow; - the scraper is mounted to rotate on the support; - the seeder includes an elastic pushing mechanism that pushes the scraper towards the ground; - the seed drill includes first and second tools, known as filling tools arranged to the right and left, respectively, of the seeding device, the right and left being defined in relation to the direction of advancement, for example a scraper and a secondary coulter, two secondary coulters or two secondary opening discs.

[0017] According to a third main embodiment, the seeder includes a said pinch roller mounted on the support, rotating, preferably freely rotating, around a pivot with axis X, so that the position of said pivot relative to the support is constant in service.

[0018] In other words, unlike the embodiment in which the seeder includes an elastic push element for the pinch roller towards the ground interposed between the support and the support arm or between the pivot and the support arm, the position of the pinch roller relative to the ground only varies if the position of the support varies relative to the ground.

[0019] In one embodiment, the fracturing tool and / or the seed drill chute is / are rigidly fixed relative to the support. When the pinch roller follows the bumps or depressions in the soil, the depth of the fissure and / or the height of the deposit of compounds, in particular seeds, through the seed drill chute remains / are constant, respectively.

[0020] Preferably, the support constitutes a strut or is rigidly fixed to a strut having sufficient flexibility to maintain pressure of the seed drill on the ground. Preferably, the strut has a "pig's tail", i.e., a coil of at least one turn, giving it this flexibility.

[0021] According to a fourth main embodiment, preferably combined with at least one other, preferably several other main aspects, preferably at least with the third main embodiment, the seeder includes a said pinch roller mounted on the support in an adjustable position.

[0022] The invention relates, in general, to an agricultural machine, preferably a seed drill according to the invention, comprising a device for adjusting the position of an accessory relative to a base, preferably a device for adjusting the position of the pivot of a pinch roller relative to a support of a seed drill according to the invention.

[0023] According to the fourth main aspect of the invention, the adjustment device preferably comprises a set of shims including one or more shims interposed between the accessory and the base in a first arrangement so as to fix a first position of the accessory on the base, the shim(s) being shaped so as to be positionable in a second arrangement so as to fix a second position of the accessory on the base, different from the first position.

[0024] As will be seen in more detail later in the description, the use of a set of shims allows for a very quick modification of the setting, in a simple way, preferably without tools, in different positions predefined by the geometry of the shims.

[0025] Many wedge shapes are conceivable by a person skilled in the art for designing such wedges. Finding a suitable shape does not present any particular difficulty.

[0026] Preferably, the wedge(s) are shaped so as to be positionable in a third arrangement so as to fix a third position of the accessory on the base, different from the first and second positions.

[0027] Preferably, the wedge(s) are shaped so as to be positionable in more than 3, more than 4, more than 5, more than 7 and / or less than 10 arrangements so as to fix as many different positions of the accessory on the base.

[0028] Said positions of the accessory on the base are preferably positions along the direction of height and along the direction of advancement, that is to say in a longitudinal plane, or "longitudinal positions".

[0029] The shape of the wedge(s) thus allows for several arrangements adapted to immobilize the accessory in different positions, preferably longitudinal. Preferably, the position of the accessory can be modified by reversing two wedges and / or changing the orientation of one or more wedges, for example by flipping them over.

[0030] An agricultural machine, preferably a seed drill according to the fourth main embodiment of the invention, may also include one or more of the following optional and preferred features: - in at least one of said arrangements, preferably in each of said arrangements, the set of wedges and optionally the base define a contact surface with the accessory which surrounds said accessory; - the base defines a housing presenting a contact surface with the set of shims, or with the set of shims and the accessory, said contact surface surrounding the set of shims, or the set of shims and said accessory, respectively; - the wedges are shaped so that, in at least one of said arrangements, preferably in each of said arrangements, the set of wedges and the accessory fill said housing without leaving any empty space; - at least one wedge, preferably each wedge, has at least one end of a shape complementary to the surface of the accessory or base or of another wedge on which said end rests, that is to say, comes to fit this surface, in at least one said arrangement; - in at least one said arrangement, preferably in each said arrangement, at least one wedge, preferably each wedge, comprises at least one end having a shape, preferably concave, complementary to a surface, preferably convex, of the accessory and / or the base and / or another wedge on which said end rests, that is to say, comes to fit this surface; the machine comprises first and second wedges, preferably identical, each comprising first and second opposite ends concave and convex respectively, shaped to fit, the accessory having a surface complementary to the surface of said first or said second end, preferably complementary to the first end; - the wedge(s) and the accessory form a stack, the machine comprising a rod fixed removably to the base and cooperating with said stack to hold it in position on the base; - the rod preferably passes through holes made through the wedge(s) and the accessory, which allows them to be immobilized in the transverse direction, that is to say in such a way as to prevent their movement to the right and / or to the left, in the transverse direction; - the stem is removable without tools; - the lower end of the stem is housed in a hole in the base, which improves the stability and robustness of the stem; - the upper end of the rod has a head, which preferably rests on the base, making it easier to grip the rod, and therefore to dismantle it; - the stem extends almost vertically; - the agricultural machine is chosen from the group formed by a seed drill, preferably a seed drill presenting one or more characteristics of the seed drill according to the other main aspects, a subsoiler, a stubble cultivator, a plow, a harrow, a hoe or a mower; - the accessory is a pivot of a wheel, preferably the pivot of a pinch roller, preferably the pivot of a pinch roller of a seed drill according to the invention; - the base is a support on which the wheel is mounted.

[0031] A set of wedges preferably allows immobilization in more than two arrangements. However, the number of arrangements is limited.

[0032] The invention therefore also relates to a kit comprising an agricultural machine according to the fourth main aspect and at least one set of additional shims, said additional shims being able to be mounted on the base in place of the shims mounted on the base, or "active shims", so as to - determine at least one additional position of the accessory on the base, said additional position being different from the first, second and optionally third positions; and / or - allow the attachment of another accessory.

[0033] By simply changing the set of shims, it is therefore possible to modify the position of the accessory.

[0034] Regardless of the main aspect considered, a seed drill according to the invention may also include one or more of the following optional and preferred features: - the seeding device comprises a main seed drill chute and a main coulter for widening the main furrow, the seed drill chute opening behind said main coulter; - the main coulter is mounted on the support via an adapter that is detachable from the support; - the main coulter is mounted on the adapter and detachable from said adapter; - the main coulter includes a tungsten carbide leading edge; - the seed drill includes, behind the seeding device, a closing wheel of said main slot.

[0035] The invention also relates to a sowing method in which a seeder according to the invention is towed in the service position and in the direction of advancement, the sowing device being used to conduct seeds into the main slot formed by the opening disc.

[0036] According to the first main embodiment, the pinch roller rolls on the ground.

[0037] According to the second main embodiment, seeds are deposited in a main slit made in the soil, and then the main slit is filled, at least partially, by making a secondary slit in the soil.

[0038] In a preferred embodiment of the second main embodiment, fertilizer is deposited in said secondary slot by means of said secondary seeder descent.

[0039] Of course, the embodiments and optional features of these different embodiments can be combined. Brief description of the figures

[0040] Other features and advantages of the invention will become apparent upon reading the detailed description that follows and upon examination of the plates of figures in which: [Fig.1] schematically represents, seen from the side, a seed drill according to an example of an embodiment of the invention, and, below this side view, the slits made in the soil by this seed drill; [Fig.2] represents a detail of the seed drill in [Fig.1]; [Fig.3] schematically represents the seed drill of [Fig.1], seen from the opposite side, the opening wheel having been removed; [Fig.4] represents a front view of a seed drill with a pinch roller, without a filling tool; [Fig.5] schematically represents the seed drill of [Fig.1], in perspective seen from below, the scraper not being visible; [Fig.6] represents a rear view of a seed drill comprising a pinch roller and a secondary coulter, without a closing wheel; [Fig.7] represents a seed drill comprising a pinch roller fixed according to the fourth principal aspect, and a strut according to the third principal aspect, seen from the front and in perspective; [Fig.8] partially represents, in perspective, the seeder of [Fig.7], the pinch roller being removed from the support arm; [Fig.9] partially represents, in perspective, three embodiments 9A, 9B and 9C of the seed drill of the [Fig.7] corresponding to three arrangements of the wedges in which the pinch roller is mounted on support arms in three different respective positions, the wedges being, for each embodiment, shown enlarged on the left of the page; [Fig. 10] represents another example of a seed drill with a pinch roller fixed according to the fourth main aspect; [Fig.1 1] partially represents, in perspective, three embodiments 11 A, 1 IB and 1 IC of the seed drill of the [Fig. 10], partially disassembled, corresponding to three arrangements of the wedges; [Fig. 12] partially represents, viewed from the housing side, four embodiments 12A, 12B and 12C in which two or three wedges are housed in the housing. Definitions

[0041] The "service position" is conventionally the position in which the seed drill is pulled by agricultural machinery, typically a tractor, on substantially level ground, so as to sow seeds into the soil. The ground is considered sufficiently firm to prevent the sinking of parts designed to bear on it, such as the closing wheels, pinch rollers, or, where applicable, scrapers.

[0042] The forward direction or "longitudinal direction" is the oriented direction F ( [Fig.l]) along which the seed drill is intended to be pulled into the service position.

[0043] A "longitudinal" distance or dimension is measured along the direction of travel. Lengths are measured along the direction of travel.

[0044] A longitudinal plane is a vertical plane parallel to the direction of advancement.

[0045] The median longitudinal plane is the longitudinal plane in which the opening disk extends.

[0046] The arrow referenced "V" is vertical and points upwards. The direction of height is the direction that is vertical in the service position.

[0047] A transverse plane is a plane perpendicular to the direction of advancement F.

[0048] A "transverse" direction T is a horizontal direction and lies in a transverse plane. Thicknesses are measured along a transverse direction. A "transverse" distance or dimension is measured along a transverse direction.

[0049] In the present description, the adjectives "lower", "upper", "horizontal", "vertical", "in front", "behind", "front", "rear", "right", "left" and "lateral" are defined with respect to the direction of advancement (arrow F therefore points "forward").

[0050] A "sliding contact" between two elements is a contact in which, in the contact zone, the two elements are not stationary relative to each other.

[0051] A part "fits" another part when, in the contact area between these parts, they have complementary shapes. The contact area is preferably greater than 100 mm², preferably greater than 200 mm², preferably greater than 300 mm², or even greater than 400 mm².

[0052] A part is "fixed" to another part when it is rigidly fixed to the latter or when its possible movements are guided. The fixing can be direct or via one or more other parts, for example via an adapter.

[0053] A contact surface between two parts "belts" the first of these parts when it forms a closed band around this first part. Such a belt helps to immobilize this first part on the second part. The first and / or the second part may be a single piece or be made up of a set of elementary parts. To determine whether the band is closed and therefore defines a continuous surface, any point interruptions at the junction between two adjacent elementary parts at the level of the contact surface are ignored.

[0054] A part, in particular a scraper, is configured to "scrape" on the ground when this part, in the operating position, is in sliding contact with the ground and bears against the ground. Alternatively, this part may, in the operating position, be in sliding contact with the ground and penetrate the ground superficially, that is to say, penetrate the ground to a depth, measured in a vertical direction, of less than 15 mm, preferably less than 10 mm, preferably less than 5 mm, preferably less than 1 mm.

[0055] The adjectives “main” and “secondary” are used for clarity purposes only.

[0056] The equivalent diameter of a section or an opening is the diameter of a disk having the same area as said section or opening.

[0057] The verbs "comprendre" or "comporter" or "présenter" must be interpreted in a non-restrictive manner, unless otherwise indicated. Detailed description

[0058] As shown in [Fig.1], in a preferred embodiment, a seed drill 10 according to the invention comprises a support 12 intended to be fixed on a cross beam 13 and on which are successively mounted, from front to back, an opening disc 14, a seeding device 15 comprising a main coulter 16 and a main seed drill chute 18, and a closing wheel 20.

[0059] Preferably, the opening disc 14, the main coulter 16, the main seed drill drop 18 and the closing wheel 20 extend substantially in a common plane, preferably vertical.

[0060] Conventionally, the opening disc 20, in its operating position and when the seed drill is being towed in the direction of travel, is intended to form a main furrow Fi in the soil. The main coulter 16 is intended to clear the soil in front of the main seed drill chute 18, and preferably to widen the main furrow. The main seed drill chute 18 is intended to guide a mixture, conventionally seeds, to the bottom of the main furrow. Preferably, it is inserted into the main furrow so as to open near the bottom of the main furrow. The closing wheel 20 is intended to close the main furrow after the mixture has been deposited in it. Preferably, the closing wheel is held against the ground by an elastic pusher, not shown.

[0061] Preferably, the various parts of the seed drill comprise, or are made of, high-yield-strength steel, or "HLE", or stainless steel. These parts may be locally reinforced with tungsten carbide and / or abrasion-resistant welding.

[0062] Support

[0063] The beam 13 conventionally includes means of attachment, not shown, to an agricultural machine, conventionally a tractor.

[0064] The support 12, which can be made up of one or more parts, is the structure which allows the other parts to be secured to the beam 13. It classically includes a fixing attachment to the beam 13.

[0065] Opening disc

[0066] The opening disc 14 is preferably discoidal in shape to ensure the opening of a continuous main slot. It is mounted for rotation, preferably free rotation, on the support 12, around a horizontal transverse axis. In one embodiment, it extends in a substantially vertical plane, which facilitates its penetration into the ground.

[0067] In one embodiment, its axis of rotation is inclined, relative to a horizontal plane, at an angle greater than 3°, greater than 5°, greater than 6°, and / or less than 10°, preferably less than 9°, preferably less than 8°. The main slot is thus inclined. This improves its performance for cutting vegetation on the ground.

[0068] The opening disc 14 preferably has a diameter greater than 10 cm, greater than 20 cm, greater than 30 cm, greater than 40 cm, greater than 50 cm, greater than 60 cm, or even greater than 100 cm, greater than 150 cm, and / or less than 250 cm, a diameter of 70 cm being preferred.

[0069] The thickness of the aperture disc 14, measured 10 mm from its peripheral edge, is preferably less than 20 mm, preferably less than 15 mm, preferably less than 10 mm, preferably less than 8 mm, or even less than 5 mm, or even less than 3 mm, or even less than 2 mm, and / or greater than 1 mm. Preferably, the peripheral edge of the aperture disc 14 is tapered.

[0070] In a preferred embodiment, the opening disc 14 carries one or two cylindrical belts 21 coaxial with the opening disc 14 and shaped to bear flat on the ground and limit the sinking into the ground.

[0071] Seeding device

[0072] The sowing device is intended for introducing the compound, preferably seeds, into the main slot. It consists of the part(s) which, in the operating position, are housed, at least partially, in the main slot.

[0073] The line which, in the service position, separates the buried part of the seeding device 15, i.e. which extends into the main slot, and the emerging part of the seeding device, i.e. which extends above the ground S, is called the "dividing line". The point of the dividing line which is furthest forward is called the "attack point" A.

[0074] Main cutter

[0075] The main coulter 16 preferably extends substantially vertically.

[0076] It preferably has a maximum thickness greater than that of the peripheral part of the opening disc used to create the main slot. Preferably, the thickness of the main coulter is greater than that of the main seed drill chute 18, which protects the seed drill chute from abrasion. This maximum thickness, measured transversely, is preferably greater than 10 mm, preferably greater than 12 mm, or greater than 14 mm and / or less than 60 mm, preferably less than 40 mm, preferably less than 30 mm. Such a maximum thickness is well suited to seed deposition.

[0077] The main coulter 16 can be mounted on the support by means of an adapter 22 detachably attached to a strut 24 of the support. Advantageously, the main counter 16 can be detached from the seed drill without having to detach the entire support, which allows coulters of various shapes to be attached to the support.

[0078] The leading edge of the main coulter, preferably tapered, is preferably inclined backwards, forming an angle [3] with a transverse plane preferably greater than 30°, 40°, 60° and / or less than 80°, 70° (see [Fig. 2]). The leading edge may be removable. Preferably, it is reinforced with tungsten carbide.

[0079] Main seed drill descent

[0080] The main seed drill chute 18, which preferably has the general shape of a tube, opens via an upper and a lower opening. The upper opening is intended to be connected to a source of the compound to be deposited, for example, a seed or plant protection product reservoir (not shown), which may be attached to the traction unit or the support 12. The lower opening 26 is intended to be positioned in the main slot, preferably enlarged or reinforced by the passage of the main coulter 16.

[0081] The equivalent diameter of the main seed drill drop is preferably greater than 5 mm, preferably greater than 8 mm, or even greater than 10 mm and / or less than 50 mm, preferably less than 40 mm, 30 mm, preferably less than 25 mm.

[0082] Closing wheel

[0083] The closing wheel 20, preferably substantially vertical, is intended to close the enlarged slot in which the compound has been deposited.

[0084] The closing wheel 20 is conventionally mounted for rotation, preferably free rotation, on the support. In a preferred embodiment, the closing wheel 20 is mounted on a suspension, for example comprising a cylinder, in particular hydraulic or pneumatic, by means of a screw or spring. The suspension is preferably shaped to elastically press the closing wheel 20 against the ground.

[0085] The closing wheel 20 preferably has a diameter greater than 10 cm, preferably greater than 20 cm, preferably greater than 25 cm, or even greater than 25 cm, greater than 50 cm, greater than 75 cm, greater than 90 cm, and / or less than 100 cm.

[0086] The width of the closing wheel 20, measured transversely, is preferably greater than 1 cm, preferably greater than 2 cm, preferably greater than 3 cm, preferably even greater than 4 cm, preferably greater than 5 cm and / or less than 10 cm, preferably less than 8 cm.

[0087] Pinch wheel

[0088] According to the first main embodiment, the seeder also includes a pinch roller 30 mounted on the support 12, rotating, preferably freely rotating, around a pivot 32 with axis X.

[0089] The pinch roller 30 preferably has an outside diameter greater than 10 cm and / or less than 50 cm.

[0090] The pinch roller 30 preferably has a thickness greater than 0.5 cm, preferably 1 cm and / or less than 10 cm, preferably 5 cm, preferably less than 2 cm.

[0091] The rolling surface of the pinch roller, i.e. the surface bearing on the ground when, in service position, the seed drill is pulled in the direction of advance, can be smooth or structured (notched in particular).

[0092] In one embodiment, the pinch roller comprises, or is made of, a polymer, preferably an elastomer, preferably a rubber. Preferably, the pinch roller is in the form of a tire, preferably including an inner tube.

[0093] On a surface into which it does not sink, the pinch roller 30 is shaped so that, in the service position, it bears along a "pinch line" LP. The pinch line can also be defined as the line formed by the points on the rolling surface of the pinch roller that are furthest, downwards, from the X axis.

[0094] The pinch line LP extends in the same transverse plane as the pivot, called the "transverse pivot plane" P32.

[0095] The pinch line is arranged in front of the seeding device 15, in particular in front of the attack point A.

[0096] Preferably, the longitudinal distance L30 between the attack point A and the pinch line LP is less than 15 cm, preferably less than 10 cm, preferably less than 5 cm and / or greater than 0.5 cm, preferably greater than 1 cm.

[0097] Preferably, the transverse distance l30 between the median longitudinal plane Pm and the pinch line is less than 15 cm, preferably less than 10 cm, preferably less than 5 cm, preferably less than 3 cm and / or greater than 0.5 cm, preferably greater than 1 cm.

[0098] The X-axis of the pivot can be horizontal. Preferably, however, the X-axis forms an angle 0 with a horizontal plane greater than 5°, preferably greater than 7°, preferably greater than 15° and / or less than 30°. Advantageously, this inclination allows the point of attack and the line of pinching to be brought closer transversely, as shown in [Fig. 5].

[0099] Preferably, the pivot 32 is mounted on the support by means of a support arm 34, the lower end of which preferably carries the pivot 32.

[0100] The support arm is preferably inclined forward, that is, its upper end is in a transverse plane that lies behind the transverse plane of its lower end. Preferably, the support arm forms, with a transverse plane, an angle a greater than 5°, preferably greater than 10° and / or less than 30°.

[0101] The support arm can be rigidly fixed to the support.

[0102] In one embodiment, the seed drill includes an elastic thrust element 38 of the pinch roller towards the ground, for example a helical spring, interposed between the support and the support arm or between the pivot and the support arm. Preferably, the force of the thrust element is adjustable.

[0103] Preferably, as illustrated in Figures 7 to 9 and according to the third main aspect, the pinch roller 30 is mounted on the support 12 such that the longitudinal position of its axis of rotation X, relative to the support, is fixed. The position of the pinch roller relative to the ground advantageously varies only if the position of the support varies relative to the ground.

[0104] Preferably, the support arm 34 is rigidly fixed to the support 12 and the pivot 32 is rigidly fixed to the support arm.

[0105] In the embodiment of figures 7 to 9, the main coulter 16 and the main seed drill chute 18 are rigidly fixed on the support 12. When the pinch roller follows the bumps or depressions on the ground, the depth of the crack and / or the height of the deposit of a compound, in particular seeds or fertilizer, in the soil, through the seed drill chute remains(s) constant, respectively.

[0106] Preferably, the support is itself rigidly fixed to a strut 24 having flexibility to maintain pressure of the pinch roller on the ground. Preferably, the strut has a "pig's tail" 61 giving it this flexibility.

[0107] In one embodiment, the support is constituted by the prop.

[0108] In the embodiment of Figures 7 to 9 in particular, according to the fourth aspect The main pinch roller 30 is mounted on the support arm 34 by means of a set of two shims 62i and 622, collectively referenced as "62", housed in a recess 64 provided in the support arm. The shims are butted against the edge of the recess.

[0109] The housing may have a solid bottom, i.e., be a blind hole, provided that the accessory is on the same side of the support arm as the housing. Preferably, the housing 64 is drilled through the support arm, in particular to form an opening, i.e., a bottomless hole, through which the accessory passes.

[0110] In a preferred embodiment, the housing 64 thus has the shape of an elongated light, preferably substantially vertical, which passes through the support arm so as to be passed through the pivot 32.

[0111] The housing is preferably shaped so that, during assembly, the wedges can be inserted into the housing on one side or the other of the support arm.

[0112] In one embodiment, the housing is shaped so that when a wedge, preferably any wedge, is inserted, along the transverse direction, into the housing, it comes into contact with the support arm, for example with a lip in the bottom of the housing or with the surface of the support arm which delimits the housing.

[0113] The wedges 62 cooperate with the housing 64 and the pivot 32 in order to prevent the latter from moving vertically or laterally relative to the support arm, i.e. in a longitudinal plane.

[0114] Preferably, to improve the quality of the pivot immobilization, - the surfaces of a hold, preferably any hold, and the housing are locally identical in the areas where said hold and the housing are in contact, and / or - the surfaces of a wedge, preferably any wedge, and the pivot are locally identical in the areas where said wedge and the pivot are in contact, and / or - the surfaces of a slipway, preferably any slipway, and an adjacent slipway are locally identical in the areas where said slipways are in contact, and / or - the surfaces of the pivot and the housing are locally identical in the areas where the pivot and the housing are in contact.

[0115] In a preferred embodiment, illustrated in [Fig.9], - the pivot has a cylindrical shape with a circular base, of diameter d; - the upper and lower ends of the housing each have a semi-cylindrical edge of diameter d, so that the pivot fits the edge of the housing when it is supported at any said end of the housing (embodiments 9A and 9B); - each wedge has, at a first end 65a, a concave surface of semi-cylindrical shape, of diameter d, and, at a second end 65b opposite to the first end, a convex surface of semi-cylindrical shape, of diameter d, so that the second end 65b of the wedge fits the edge of the housing when it is supported at any said end of the housing, or fits the first end 65a of an adjacent wedge when it is supported on said adjacent wedge (embodyments 9A and 9B).

[0116] Preferably, a shim, preferably each shim is shaped to bear against the edge of the housing with a bearing surface whose dimension, along the thickness direction, is greater than 5 mm, preferably greater than 8 mm, preferably greater than 10 mm, which improves the retention of the shim and contributes to robustness of the seed drill, the maximum thickness preferably being less than 20 mm, preferably less than 15 mm.

[0117] In one embodiment, illustrated in [Fig.9], a wedge, preferably each wedge, is shaped to fill the housing over its entire depth, preferably to fit the housing over the entire depth of the housing.

[0118] Preferably, one, preferably each wedge fits snugly around the edge of the housing.

[0119] The shims 62 may have the same length, measured between their first and second ends, as in [Fig. 9], or may have different lengths, depending on the desired positions for the pivot. For example, when the shim set includes two shims of the same length, as in [Fig. 9], the pivot may be at either end of the housing or at mid-length of the housing. When the shim set includes two shims of different lengths, as in [Fig. 9], the pivot may be at either end of the housing or in two intermediate positions, depending on whether the longer shim is below or above the pivot.

[0120] In a preferred embodiment, the wedges are shaped so that at least when the housing is viewed from the side, as in [Fig.9], the housing is filled by the wedges and the pivot, preferably regardless of the arrangement of the wedges and the pivot.

[0121] In one embodiment, as illustrated in [Fig.9], the wedges are all identical.

[0122] Preferably, to prevent the wedges and the pivot from moving transversely, and in particular to prevent the wedges from coming out of the housing, the support arm 34, the wedges 62 and the pivot 32 have respective orifices 6834, 6862 and 6832, and a rod 66, preferably vertical, passes through said orifices, as illustrated in [Fig.8].

[0123] Preferably, the upper end of the rod 66 has a head 69 which rests on an upper plate 70, substantially horizontal, of the support arm and the lower end of the rod 66 fits into a hole 71 provided in a lower plate 72, substantially horizontal, of the support arm.

[0124] A pin 74, preferably of the "beta pin" type, passes, preferably substantially horizontally, through an orifice 75 in the shaft 66, immediately below the upper plate 70, thus preventing the shaft 66 from being extracted from the orifices 6862 and 6832, particularly when using the seed drill. The pin 74 is removable, allowing the shaft 66 to be extracted and the shims and pivot to be disassembled, particularly to adjust the pivot height.

[0125] Other means of preventing the wedges and the pivot from moving laterally may be considered.

[0126] In one embodiment, one or more sets of "additional" shims, comprising one or more so-called "additional" shims, are available for These shims, or "active shims," ​​can be substituted for the shims currently in position on the seed drill to immobilize the pivot in at least one other position, and / or to secure a pivot of a different shape. By simply changing the shims, it is thus possible to modify the pivot's position and / or mount a pivot of a different shape.

[0127] The implementation of the fourth main aspect follows directly from the preceding description.

[0128] Initially, the pinch roller is removed from the support arm and a set of shims is selected, depending on the desired position for the pivot 32. For example, shims 62i and 622 of [Fig. 9] are selected if one of the three positions of embodiments 9A, 9B, and 9C is desired. The shims and the pivot are then arranged in the housing, in this case stacked one on top of the other, in an arrangement according to the desired position for the pivot 32. For example, to fix the pivot in the upper position, the pivot is placed above shim 62b, which is itself placed above shim 622, both shims being oriented with their concave ends facing upwards (embodyment 9A). To fix the pivot in the lower position, the pivot is placed below the shim 62b which is itself placed below the shim 622, both shims being oriented with their concave end downwards (embodyment 9B).To fix the pivot in an intermediate position, the pivot is placed between shim 62i and shim 622, with the concave ends of the two shims facing each other (embodiment 9C). In these three embodiments, the shims and the pivot interlock and form an assembly that fits precisely into the housing, thus providing high stability. In other words, regardless of the arrangement of the shims and the pivot, the edge of the housing is in continuous contact with this assembly and surrounds it.

[0129] Regardless of the arrangement of the shims and the pivot, the shims, the pivot and the housing cooperate to completely fill the housing, leaving substantially no gap between them, which further improves the rigidity of the assembly.

[0130] Furthermore, regardless of the arrangement of the shims and the pivot, the shims alone (embodiment 9C), or a shim in cooperation with the edge of the housing (embodiments 9A and 9B) define a continuous contact surface with the pivot and the belt.

[0131] The axis of the shims' holes 6862 and the pivot's hole 6832 are aligned with the axis of the support arm's hole 6834 and the hole 71. The lower end of the rod 66, opposite the head 69, is then inserted through the support arm's hole 6834, then through the shims' holes 6862 and the pivot's hole 6832, until it enters the hole 71. The downward movement of the rod 66 can be blocked by the head's stop. 69 on the upper face of the upper plate 70 and / or by the stop of the lower end of the rod 66 on the edge of the hole 71. Preferably, the diameter of the part of the rod that passes through the orifice 6834, the orifices 6862 of the shims and the orifice 6832 of the pivot is substantially equal to the diameter of these orifices, and, preferably, the end of the part of the rod that enters the hole 71 fits snugly against the edge of this hole, so that any movement to the right or left of the shims and the pivot is blocked.

[0132] The pin 74 is then inserted into the hole 75 and, being a beta pin, is locked in position on the rod 66 by its complementary shape with the rod 75. Furthermore, the pin extends just below the upper plate 70 so that any upward movement of the pin is hindered by the pin's stop against the upper plate 70. The pin thus prevents any extraction of the rod 66 and keeps the shims and the pivot assembled in the housing 64.

[0133] Disassembly is carried out by reverse operations.

[0134] After disassembly, the order and / or orientation of one or more of the wedges can be modified to achieve other possible positions with the wedges, or to adapt to another pivot shape.

[0135] The set of shims can also be replaced by another set of shims, i.e. an additional set, in order to position the pinch roller in other predefined positions or for fixing another pivot.

[0136] Of course, the fourth main aspect is not limited to the embodiments described and represented, which are provided for illustrative purposes only.

[0137] In particular, the fourth main aspect is not limited to a seed drill, but extends to any agricultural machine. Except for technical incompatibilities, the characteristics described for the agricultural machine are applicable to the seed drill described in this description, and vice versa.

[0138] The detailed description of the fourth principal aspect refers to a housing provided in the support arm. The housing could also be provided in the support if the support arm is rigidly fixed to the support, or is integrated into the support.

[0139] The fourth main aspect is not limited to the position adjustment of a wheel pivot, and even less to a pinch roller pivot; it extends to the position adjustment of any accessory, the latter being able in particular to belong to, or be made up of, an opening disc, a seeding device, or a filling tool, for example a seed drill drop, a coulter, a closing wheel, a scraper or a cracking tool like those described above.

[0140] The accessory may be in particular a handle of an agricultural tool, or more generally any gripping element of an agricultural tool.

[0141] The shape of the housing may differ from that described and illustrated. The wedges are not necessarily stacked one on top of the other. For example, they may be arranged in several stacks placed side-by-side.

[0142] Fig. 12 illustrates, for example, four other embodiments of wedges housed in the housing.

[0143] In embodiment 12A, the two wedges define three positions. By reversing the two wedges, three other positions are possible. The two wedges can be merged into one, for the same result.

[0144] In embodiment 12B, the two shims 62i and 622 define three possible positions for the pivot. Interchanging these two shims with shim 623 allows for three additional positions to be defined.

[0145] In embodiment 12C, the two shims 62i and 622 are different and define three possible positions for the pivot, none of these positions being centered at mid-length of the housing.

[0146] In the 12D embodiment, a single wedge, in the arrangement shown, defines three positions for the pivot. It can be flipped vertically (the visible face becoming the hidden face, and vice versa) and / or horizontally (the highest end becoming the lowest end, and vice versa), which allows for four different arrangements, and therefore twelve possible positions for the pivot.

[0147] The shims are not necessarily of complementary shape with the pivot or with the housing, as in embodiment 12A.

[0148] Unlike a wedge, the accessory belongs to a device having an agricultural function, in this case a pinching device.

[0149] A set of shims, whether active or additional, may consist of only one shim. Preferably, it comprises several shims, preferably two or three shims.

[0150] In one embodiment, the set of wedges comprises only a single wedge. This single wedge is integrated into a pivot device 76, preferably such as that illustrated in [Fig. 10], which comprises - a single 62 H wedge in the shape of a bar, preferably of square section, with axis Y, - the pivot, with axis X, not coincident with axis Y, preferably parallel to axis X, and - a support plate, preferably perpendicular to axis Y, on the two large faces of which are rigidly fixed, preferably welded, the wedge and the pivot, respectively.

[0151] In one embodiment, the wedge is shaped to be housed in the housing, in this case a square-shaped opening, complementary to the wedge which enters it. The wedge can thus be positioned in the housing in four "arrangements » different, in which it is oriented in four respective angular orientations, around its Y axis, two by two equiangularly separated by 90°.

[0152] This results in four corresponding positions for the pivot axis.

[0153] The square shape of the light and the wedge is not limiting. For example, any regular polygon shape, for example triangle or pentagon, can be considered, for example for three or five different positions.

[0154] A rod 66 is provided to lock the pivot device in position on the support arm. It passes through an orifice 6862 which passes through the wedge 62i on the side of the support arm opposite the pivot 32.

[0155] Not all shims are necessarily inserted from the same side of the housing.

[0156] For example, in the embodiment of [Fig. 10], the set of wedges comprises two wedges 62i and 622 which are each introduced on a respective side of the housing.

[0157] In one embodiment of [Fig. 10], the square-section wedge 62b is shaped to fit into the housing, in this case a horizontally extending rectangular opening, in which it can slide. The wedge 622 complements the wedge 62i to fill the housing.

[0158] For the same orientation of the wedge 622, the wedge 62i can be positioned in the housing in four different "arrangements", in which it is oriented in four respective angular orientations, around its Y axis, two by two equiangularly separated by 90°. [Fig. 11] illustrates three of these orientations.

[0159] If the shim 622 is asymmetrical, it is possible to change the position of the Y axis by turning the shim 622 over. The shim 62i can then still be positioned in the housing according to the four angular orientations around the Y axis, which offers four other positions for the X axis of the pivot.

[0160] A person skilled in the art can easily conceive of other variants. For example, if the shim 62i can move in the housing from top to bottom and from right to left, and then be blocked with a third shim, the shim 622 can be shaped to offer eight additional positions for the pivot axis.

[0161] The shapes of the housing and the wedges can thus be chosen according to the positions and the number of positions desired for the pivot axis.

[0162] Filling tool

[0163] According to the second main embodiment, the seed drill also includes a filling tool. The filling tool is intended, in the operating position and when the seed drill is being towed in the direction of travel F, to fill, at least partially, the main furrow into which seeds have been deposited by means of the main seed drill's descent.

[0164] The filling tool is therefore arranged on the support so as to fill the main gap after a compound has been deposited there by the seeding device.

[0165] The action of the filling tool can be complemented by the action of the closing wheel.

[0166] The filling tool is configured so that, in the operating position, it is in sliding contact with the ground, so as to exert a dynamic action tending to push soil into the main furrow. Preferably, the longitudinal distance between the area of ​​the filling tool in sliding contact with the ground and the lower opening 26 of the main seed drill chute is less than 30 cm, 20 cm, 1 cm and / or greater than 0.5 cm.

[0167] Cracking tool

[0168] In one embodiment, the filling tool is a fracturing tool configured to create a secondary slit F2 in the soil, parallel to the main slit. The transverse distance 142 between the two slits must be sufficiently small so that the creation of the secondary slit transfers soil initially located between the two slits into the main slit. Preferably, the transverse distance 142 between the main coulter and the fracturing tool is greater than 1 mm, 3 mm, 5 mm, 10 mm and / or less than 50 mm, 40 mm, 30 mm, 20 mm, preferably less than 15 mm. In one embodiment, this distance is substantially zero, meaning that the fracturing tool scrapes a lateral wall of the main slit. The creation of the secondary slit thus widens the main slit, while simultaneously causing soil to fall into the main slit.

[0169] Preferably, the fracturing tool is configured to create a secondary slit with a volume greater than 0.5, 0.7, 0.9, 1.1, 1.5, or 2 times and / or less than 5 times the volume of the main slit, thus ensuring significant earth displacement for filling the main slit. Preferably, the fracturing tool has a thickness greater than 1 mm, preferably greater than 5 mm, preferably greater than 10 mm or 15 mm and / or less than 30 mm, preferably less than 20 mm.

[0170] For the same reason, preferably, the cracking tool is configured to create a secondary crack whose depth is greater than 0.5, 0.7, 0.9 times and / or less than 2, 1.5 or 1.2 times the depth of the main crack.

[0171] Preferably, the cracking tool is configured to provide a secondary slot substantially parallel to the main slot, which allows for substantially uniform action over the entire height of the secondary slot.

[0172] According to a preferred embodiment illustrated in [Fig. 4] or [Fig. 5], the seeder comprises a secondary seed drill chute 40 configured for depositing a compound, preferably a fertilizer, preferably in the form of granules, or Alternatively, the fertilizer can be applied in liquid form in the secondary slot. Advantageously, the seeder can be used to simultaneously sow seeds and deposit fertilizer. The formation of two separate slots advantageously prevents any contact between seeds and fertilizer.

[0173] In particular when the secondary seed drill drop is configured for fertilizer deposition, the fracturing tool is preferably configured to create a secondary slit whose depth is greater than 1 times and / or less than 2, 1.5 or 1.2 times the depth of the main slit, as shown in [Fig.6].

[0174] The cracking tool may in particular be a secondary coulter 42.

[0175] Preferably, the secondary coulter 42 has a thickness greater than 1 mm, preferably greater than 5 mm, preferably greater than 10 mm or 15 mm and / or less than 40 mm, preferably less than 30 mm, preferably less than 20 mm.

[0176] The transverse distance 14 2 between the main coulter and the secondary coulter is preferably less than 10 mm and greater than 5 mm, the main and secondary coulters preferably extending parallel to each other. In other words, the main and secondary coulters extend side by side with respect to the direction of travel F of the seed drill.

[0177] The secondary coulter preferably extends in a general plane having, in the operating position and at ground level, an inclination, relative to a vertical longitudinal plane, of less than 30°, preferably less than 15°, preferably less than 10°, less than 5°, preferably substantially zero. Preferably, the secondary coulter has the same inclination as the primary coulter.

[0178] The leading edge 44 of the secondary coulter 42, preferably tapered, is preferably inclined backwards, forming an angle [3'] with a transverse plane preferably greater than 30°, 40°, 60° and / or less than 80°, 70° (see [Fig. 3]). The angle [3'] may be identical to the angle [3.

[0179] The leading edge 44 can be removable. Preferably, it is reinforced with tungsten carbide.

[0180] Other fracturing tools besides a coulter are possible. In particular, the fracturing tool can be a secondary opening disc, acting like the opening disc of the main slot. The characteristics described above are applicable to such a secondary opening disc. In particular, the seed drill can include two secondary opening discs, allowing two secondary slots to be created on either side of the main slot so as to at least partially fill it. A secondary coulter is preferred to meet the constraints of size and ease of manufacture.

[0181] Scraper

[0182] The filling tool can be a scraper 50 configured to rub against the ground and push soil towards the main slot. The bearing surface of the scraper on the ground is referenced as S50 in [Fig. 1].

[0183] The scraper may include a contact plate 52 provided so that, in the service position, the scraper rubs against the ground via this contact plate.

[0184] Preferably, the transverse dimension of the scraper, in particular of the contact plate, is greater than 10 mm, preferably greater than 30 mm, preferably greater than 60 mm and / or less than 100 mm. Preferably, the transverse dimension of the scraper is greater than the transverse dimension of the main coulter.

[0185] Preferably, the longitudinal dimension of the scraper, in particular of the contact plate, is greater than 10 mm, preferably greater than 40 mm, or even greater than 100 mm and / or less than 150 mm.

[0186] Preferably, the transverse distance between the main coulter and the scraper is less than 20 mm, preferably 10 mm, and preferably 5 mm. In a preferred embodiment, as shown in [Fig. 1], this distance is substantially zero, meaning that the scraper comes into contact with the edge of the main slit. The scraper thus scrapes the edge of the main slit. The scraper is preferably aligned with the main coulter along the direction of travel.

[0187] The longitudinal distance L50 separating the attack point A and the scraper is preferably less than 50 cm, preferably less than 30 cm and / or greater than 10 cm or 20 cm.

[0188] Preferably, the scraper 50 is pivotally mounted on the support, preferably around a pivot with a transverse horizontal axis. Preferably, its weight is sufficient to keep it against the ground when the seed drill is towed in the direction of travel. The pivot of the scraper is preferably, in the direction of travel, in front of the scraper's bearing surface S50 on the ground.

[0189] The scraper can also be mounted on a suspension, not shown, for example comprising a cylinder, in particular hydraulic or pneumatic, by screw or spring. The suspension is preferably shaped to allow vertical movement of the scraper and to press it elastically against the ground in the operating position. Advantageously, the scraper's contact with the ground is maintained even when the seed drill is subjected to shocks. Preferably, the stiffness of the suspension is adjustable.

[0190] A seed drill chute can also be provided behind the scraper, in particular for spreading liquid fertilizer on the soil surface.

[0191] The seed drill may of course include several filling tools, and in particular a scraper and a secondary coulter, or two secondary coulters extending on either side of the main coulter relative to the median longitudinal plane. The secondary coulters may be identical or different.

[0192] Operation

[0193] The operation of a seed drill according to the invention results directly from the preceding description.

[0194] The support is fixed to the beam 13, which itself is attached to a tractor, then pulled over the field to be sown, according to the direction of advancement.

[0195] The opening disc 14 gradually penetrates the soil until the belt 21 limits this penetration. As it advances, the opening disc 14 creates a narrow main groove Fi. The opening disc 14 acts like a pizza cutter. Advantageously, the soil does not need to be prepared.

[0196] The main coulter 16, housed in the main slot, preferably has a thickness greater than the width of the slot. It therefore helps to widen and strengthen it, which facilitates the deposition of seeds at the bottom of the main slot.

[0197] Seeds G are then progressively sown into the enlarged main slot, via the main seed drill descent 26.

[0198] Plant material 60 (symbolized by a dashed oval in [Fig. 1]) can, however, become interposed between the opening disc and the main coulter. This plant material is pinched between the ground and the pinch roller. This pinching, along the pinch line LP, is essentially localized and allows the plant material to rotate when it comes into contact with the main coulter at the point of contact A, as shown in [Fig. 1]. This blocking of the plant material advantageously facilitates its rotation on the ground (thick arrow in [Fig. 1]). It can thus bypass the main coulter and avoid accumulating.

[0199] After a seed has been deposited in the main slot, the main slot is at least partially filled with the sliding contact filling tool(s).

[0200] In particular, a secondary furrow F2 is created by the secondary coulter, near the main furrow. The soil between these two furrows is thus pushed towards the main furrow. Preferably, granular fertilizer E is spread into the secondary furrow via the secondary seed drill chute 40.

[0201] The scraper 50 rubs on the ground S, near the main slot, so as to push soil back into the main slot.

[0202] The closing wheel 20 finally rolls over the slot, which is at least partially filled, to close it even more.

[0203] Tests have shown that a seeder according to the invention does not cause significant plant blockages in front of the sowing device. It leaves behind a substantially flat surface, in which the main slot is well closed, which prevents birds from eating the sown seeds and facilitates germination.

[0204] Of course, the invention is not limited to the embodiments described and represented, which are provided for illustrative purposes only.

Claims

Demands

1. Agricultural machine comprising a device for adjusting the position of an accessory (32) relative to a base (12), the adjustment device comprising a set of shims having one or more shims (62i, 622) interposed between the accessory and the base in a first arrangement so as to fix a first position of the accessory on the base, the shim(s) being shaped so as to be positionable in a second arrangement so as to fix a second position of the accessory on the base, different from the first position.

2. Machine according to the immediately preceding claim, in which the wedge(s) are shaped so as to be positionable in a third arrangement so as to fix a third position of the accessory on the base, different from the first and second positions.

3. Machine according to any one of the preceding claims, wherein, in at least one said arrangement, preferably in each said arrangement, the set of wedges and optionally the base define a contact surface with the accessory which surrounds said accessory.

4. Machine according to any one of the preceding claims, wherein the base defines a housing having a contact surface with the shim set, or with the shim set and the accessory, said contact surface encircling the shim set, or the shim set and said accessory, respectively.

5. Machine according to the immediately preceding claim, in which the wedges are formed so that, in at least one said arrangement, preferably in each said arrangement, the set of wedges and the accessory fill said housing without leaving any empty space.

6. Machine according to any one of the preceding claims, wherein at least one wedge, preferably each wedge, has at least one end (65a, 65b) of a shape complementary to the surface of the accessory or base or of another wedge on which said end rests in at least one said arrangement.

7. Machine according to any one of the preceding claims, wherein, in at least one said arrangement, preferably in each said arrangement, at least one wedge, preferably each wedge, comprises at least one end (65a) having a concave shape, complementary to a convex surface of the accessory and / or the base and / or another wedge on which said end rests.

8. Machine according to any one of the preceding claims, comprising first and second wedges, preferably identical, each comprising first and second opposite ends concave and convex respectively, shaped to fit together, the accessory having a surface complementary to the surface of said first or said second end, preferably complementary to the first end.

9. Machine according to any one of the preceding claims, wherein the wedge(s) and the accessory form a stack, the machine comprising a rod (66) removably fixed to the base and cooperating with said stack to maintain it in position on the base, the rod (66) preferably passing through orifices (6862, 6832) formed through the wedge(s) and the accessory.

10. Machine according to any one of the preceding claims, selected from the group consisting of a seed drill, a subsoiler, a stubble cultivator, a cultivator, a plow, a harrow, a hoeing machine or a mower.

11. Machine according to any one of the preceding claims, - said machine being a seed drill, - the accessory being a pivot (32) of a wheel (30); and - the base (12) being a support (12, 34) on which said wheel is mounted.

12. Kit comprising a machine according to any one of the preceding claims and at least one set of additional shims, said additional shims being able to be mounted on the base in place of the shims mounted on the base, so as to - determine at least one additional position of the accessory on the base, said additional position being different from the first, second and optionally third positions; and / or - permit the attachment of another accessory.