RU2789542C1 - Agricultural seeder with material pipeline of variable length - Google Patents

Abstract

FIELD: agricultural machinery.

SUBSTANCE: invention relates to an agricultural seeder with a frame and several seeding units and seed separation devices movably installed on the frame. At the same time, seeding units have at least one ploughshare (10), one material pipeline (14) for supplying seed material from the separation device to a planting zone with hole (16) located close to the soil, and one pressing element. At least one ploughshare (10), hole (16), and the pressing element are located in the seeding unit in this working sequence, and the seed separation device, without mechanically rigid connection, is movably connected to the machine frame, using a corresponding device of the seeding unit. The material pipeline consists of two tubular sections (26, 27), which can telescopically retract to each other in at least one section (30). Retracting section (30) of telescopic tubes (26, 27) is in a lower part of material pipeline (14). Ploughshare (10) is one or two disc ploughshares (32). Retracting section (30) of telescopic tubes (26, 27) is completely located, if view the seeder from side, inside a circumference formed with one or several disc ploughshares (32), or it partially protrudes from it.

EFFECT: invention allows for an increase in the reliability of protection of a telescopic tube from penetration of clods and stones.

19 cl, 4 dwg

Description

The present invention relates to an agricultural planter with a frame and several metering units and devices for separating seeds, movably mounted on the frame, and the metering units have at least one coulter, one material conduit for supplying seed material from the device for separating to a planting area with an opening located close to the soil, and one pressing element, while at least one coulter, a hole and a pressing element are located in the sowing unit in this working sequence, and the device for separating seeds without mechanically rigid connection is movably connected to the frame of the machine using appropriate sowing device.

From US Pat. No. 5,603,269 a planter is known in which a seed separating device is rigidly connected to the frame of the machine. Since the metering units are movably connected to the frame, they can move over uneven ground during operation and tilt up when in contact with foreign objects. Due to the lack of connection to the sowing units, the constant vertical movements of the units are not transferred to the device for separating the seeds. As a result, they are less affected by shocks, the separation of the seeds remains relatively accurate. However, it turned out that the disadvantage is that the material conduits must be very long to compensate for the relative movements of the metering units and the device for separating the seeds. Due to the length and movements of the material pipelines, the seeds travel different distances, which leads to uneven sowing. In addition, sowing results are degraded due to the constant deformation of the material pipeline.

US Pat. No. 4,074,830 describes another planter in which a seed separating device is rigidly connected to a seed meter. The material line between the seed separator and the meter can be shorter. In any case, due to the constant vertical movements of the corresponding metering unit, the seed separating device is constantly subjected to constant shocks and shocks, which lead to errors in separating the seeds and, as a result, to errors in sowing the seeds in the row.

In WO 2009/043853 A1, some figures show typical seed drills in which a sowing unit and a seed box with a fixed seed separating device are rotatably connected to the frame of the machine. The meter and seed box are not rigidly connected to each other, so when the meter moves vertically, they do not move up and down in the same way and with a rigid connection between them. With these seeders, the material lines are blocked in certain areas, so that seeds are not delivered in these areas. In some embodiments, sections of material conduits enter the upper part of the material conduit without contact with the intersection. Due to the location of these sections in the upper part of the material conduit in the material conduit, a strong pressure drop and air flows across the direction of seed movement occur in the material conduit even in the seed acceleration zone, due to which the seeds deviate from the optimal trajectory and can be sown inaccurately.

In general, the disadvantage of the solutions known from the prior art is that the seeds coming from the opening must be closed as precisely as possible on or in front of the pressing element in order to prevent errors in placing the seeds in the row. When the seed separating device and the metering unit are moved relative to each other, the position of the material conduit with the hole relative to the pressure element changes, due to which the seeds fall on the pressure element, in front of or next to it at different places.

The purpose of the present invention is to improve the accuracy of seed placement and reduce the number of errors in the supply of seed material. With more precise seed separation and placement, as well as fewer errors when applying to the soil, you can increase the speed of the planter during work. The material pipeline should be such that differences in length are compensated for without increasing the number of errors in seeding.

This task is solved by a typical seeder, in which the retractable section of the telescopic tube is located in the lower part of the material conduit.

With such an arrangement of the sliding part of the telescopic tube in the lower part of the material conduit, the acceleration of the seeds in the upper part of the material conduit does not deteriorate. According to one embodiment of the invention, the retractable part of the telescopic tube can even be located in the lower third of the material conduit. The air entering the upper part of the material conduit along with the seeds has the same pressure, direction of flow and speed without changes there. Thanks to this, the seeds get a very good acceleration. They move precisely along the optimal trajectory, as they are not deflected by transverse air flows. In the lower half of the material conduit, the seeds have already reached their maximum speed, at which they have a relatively high kinetic energy. Due to this, the seeds do not easily deviate from the optimal trajectory in the material pipeline due to disturbing influences. Since the seeds are in the lower half of the material pipeline for a very short time during the feeding, disturbances have little effect on their trajectory, so that the effect on the flow and direction of the seed supply in the lower part of the material pipeline is much less. Thus, if the air flows are unstable or the inner surface of the wall of the material conduit changes in the area of the retractable part of the telescopic tube, this practically does not affect the trajectory of the seeds in the material conduit.

Due to the possibility of changing the length of this section, the material pipeline can be adapted to the current distance between the seed separator and the meter. In particular, if one end of the material conduit is rigidly connected to the seed separating device, and the other end to the metering unit component. Due to the possibility of changing the length in this design, the length of the material conduit is always almost or exactly equal to that required to connect the seed separator to the meter, since the length of the material conduit always changes properly with vertical movements of the seed separator and the meter due to changes in the length of the corresponding part of the material conduit . By changing the length of the material conduit according to a certain value required at a particular moment, especially by shortening the material conduit, the seeds are less braked by friction and come out of the hole at a higher speed, i.e. they stay in the material conduit for less time. The shorter material path is also closer to the ideal direct connection between the seed splitter and the meter; due to the shorter path of the seeds through the material pipeline, they stay there for a shorter time compared to longer material pipelines. Less friction and a shorter delivery path result in less variation in seed placement accuracy.

Since, in the design of the material line according to the invention, a direct and rigid connection between the seed separating device and the sowing unit is no longer required to shorten the material line, the vertical movements of the sowing unit are no longer transmitted to the seed separating device. In addition, vertical movements no longer lead to a change in the free cross-section of the material conduit when its walls are bent and unbent or broken. Such movements can lead to a complete blockage of the seed supply in the corrugated tubes, which, in turn, will lead to incorrect sowing. The seed separating device can only be operated under favorable conditions in which the required separation quality can be achieved.

By using a line with a variable length, the number of places of incorrect seeding is reduced. The feed rate of seeds in the material pipeline becomes more uniform and fluctuates less for individual seeds, which generally allows to increase it. Due to the higher seed feed rate, it is possible to achieve sufficient sowing accuracy even at higher seed drill speeds.

Another advantage of the invention is that when the seed is supplied, the opening in the material conduit is always approximately in the same position relative to the pressing element. Since the length of the material conduit changes, and the spatial position of the hole relative to the pressing element remains constant, the trajectories of the seeds in the material conduit relative to the pressing element also remain constant, which ensures approximately constant application and pressing of seeds in the soil.

In general, the above effects provide an increase in the efficiency of the seeder. It can work at a higher speed and with higher seeding accuracy.

When it comes to the fact that the seed separating device is movably mounted on the frame of the machine, this does not mean that only this component has a movable connection to the frame. The seed separating device can also be part of an assembly, for example in combination with a tank. In this case, the assembly in which the device for separating the seeds is located is movably connected to the frame of the machine along with this device.

When it comes to the movable connection of the sowing unit with the frame of the machine, this should also be understood in such a way that only individual parts of the sowing unit or each part of it can be movably connected to the frame.

When this description refers to a metering unit, it does not have to be a single unit. From a functional point of view, this term should be understood as a general designation of an assembly with such main components as a coulter, a material pipeline and a pressing element designed to open a furrow, place seeds in a furrow and then press. Before and/or after these main components, there may be other parts of the machine that perform auxiliary functions, such as height wheels, blades or rollers, adjusters, frame parts, drives, and so on. Each of the parts related to the meter can be connected to the frame of the machine, or part of the machine can be located separately in the planter, and other parts can form a unit. The main components of the metering unit can be movably connected to the machine frame individually, as a partial combination or all together.

Instead of a pressing element in the form of a roller, a blade or similar element designed to embed the seeds in the soil can be used. The sowing unit can be designed so that the coulter and clamping element are in a common rigid or movable frame; in addition, the coulter and the pressing element can be movably connected to the frame of the machine separately, so that they can move independently of each other or with an articulated joint.

One metering unit can have one or more coulters. Coulters can be located individually or in pairs. The coulters can be fixed or be a single or double rotating disc in a V-shaped design, pointed in the direction of travel.

The annulus, or vents formed therein between the telescopic tubes, may be used to vent compressed air from the material conduit in a section downstream of the seed separating device where the seeds have already been sufficiently accelerated by the compressed air so that the air does not interfere with seed placement into the soil and did not blow off the seeds, however, without interrupting the seed supply. The transition between tube sections can also be used to create turbulence in the air stream by targeted air supply or air removal from the material pipeline in order to prevent errors in seed placement caused by air currents. The air flow rate in the material conduit can be reduced by increasing the cross section of the material conduit, at least in the transition zone between the telescopic tubes.

Preferably, the material conduit is made of rigid tubular sections which can be pushed into each other telescopically in at least one section. If there are two sections sliding into each other, they naturally move telescopically in only one section. If there are more than two sections of the material conduit, of course, there may be more sections into which the pipe sections can be pushed. With the help of telescopic sections sliding into each other, if necessary, you can change the length of the material pipeline.

According to one embodiment of the invention, the coulter is one or two disc coulters, and the retractable portion of the telescopic tube is - when viewed from the side of the planter - completely inside the circle formed by the disc coulters or partially projecting beyond it. With this arrangement, the retractable section of the telescopic tube is reliably protected from lumps and stones thrown by the disc openers, which could damage and contaminate it. Plant residues in the field also cannot easily accumulate around the material conduit and create tensile and bending loads in this section of the material conduit that would impede the movements of the telescopic sections in this area.

In accordance with one embodiment of the invention, on the outer side of the material conduit in the region of the sliding section of the telescopic tube, there is a cuff for sealing the telescopic connection. It is designed to protect the sliding surfaces of the tubes from sand, which can make it difficult to move them. The cuff can also be gas-tight, so that air cannot escape from the material conduit in the area of the retractable section of the telescopic tube. This is necessary to prevent pressure drop and turbulence in this section of the conduit. In this case, the gap between the sliding surfaces during the movement of the telescopic tube can be larger, and the air flow in the material conduit will not change for the worse. With an increase in the gap between the sliding surfaces, the telescopic tube moves more easily, since the friction force between them decreases. In some parts of the collar, there may be a bellows to adapt the collar to changes in the length of the material conduit.

In yet another embodiment of the invention, the retractable section has at least one inner and one outer part of the telescopic tube, the outer part being in the material path direction after or below the inner part. Thus, in the direction of seed supply, there are no inner edges in the tube that could deflect or trap the seeds.

In one of the embodiments of the invention, the part of the material conduit, which has a sliding section of the telescopic tube, is connected to the support ski. It protects the telescopic tube from collisions with clods of earth, stones and plant debris. In addition, it prevents bending and shearing forces from soil, stones and/or plant residues on the retractable portion of the telescopic tube. This reduces the risk of damage to the material pipeline. At the same time, sowing accuracy is increased, as the material pipeline can make fewer movements.

In one embodiment of the invention, the ski is movably connected to the frame of the machine so as to move relative to it. Relative movements of the ski can be provided, in particular in the vertical direction, so that the material conduit can also move in it. To do this, the ski can be directly connected to the coulter and (or) the frame of the machine and (or) the clamping element with a rigid connecting element or a movable lever.

In one embodiment of the invention, the bent section of the material conduit is connected to a retractable movable section of the telescopic tube. Thus, the telescopic movement is carried out exactly or almost exactly vertically. The seeds deviate from the vertical direction of fall and acceleration towards the pressing element only after the movable section of the telescopic tube. Thanks to this, the seeds in this part are guided and move without interference.

In one embodiment of the invention, the length of the material conduit is changed due to a section of the material conduit made of an elastic material, the inner surface of the elastic section being in the form of a hose.

Due to the shape of the section hose made of elastic material, there are no sections on the inner surface of this section, the shape and direction of which could give the seeds an interfering impulse that deflects the seeds from the trajectory set by the material pipeline. As an elastic material for this section can be used, in particular rubber or elastomer. This material is resilient enough to withstand repeated elongation and contraction over the life of the planter. An elastic material is capable of changing shape under the action of force, and when the force is stopped, it can return to its original shape. The elastic of this section of material conduit must be sufficient to compensate, dampen and/or damp vibrations that occur between the seed separator and the meter during planter operation. This requires the right material and the right wall thickness. Since there are no sections on the inner surface of the section made of elastic material, the shape and direction of which could give the seeds an interfering impulse that deviates the seeds from the general trajectory set by the material pipeline, failures in the seed flow are prevented. The general trajectory set by the material pipeline is understood as the trajectory of the seed in the material pipeline. The overall trajectory is the trajectory obtained when the seed follows the shape of the inner surface of the material conduit without much deviation as a result of the action of physical forces, such as mass, gravity, speed, friction, air flow velocity, air resistance, etc. ... On individual sections of the trajectory can be straight or curved, but should not have sharp turns, jumps and shifts.

Surfaces, the shape and direction of which gives the seeds an interfering impulse, are surfaces that deviate the seeds from the general trajectory specified by the material pipeline, as a result of which the seed touching such a surface switches to a trajectory that differs from the general one. An interfering impulse can transfer the seed to a trajectory at an acute or right angle to the general one, can change the position of the actual vertical trajectory, or be a combination of such impulses. Such impulses can be caused, in particular, by protrusions in the region of the fold ribs of the bellows or by thickenings of the rounded transitions of the folded material. Interfering impulses can slow down the seeds in the material conduit, which will move, hit one or more times on the inner wall of the material conduit, come into uncontrolled or oscillatory motion. In all these cases, the seed moving in this way cannot be planted in the furrow in the right place and at the right frequency necessary for accurate sowing.

In one of the embodiments of the invention, the inner surface of the section, made of elastic material, does not have folds and waviness. Folds and waves have a particularly strong effect on the movement of seeds along the material pipeline. Their absence prevents interference with the supply of seeds through the material pipeline.

In one embodiment of the invention, a section made of an elastic material has a constant internal cross-section along its entire length. Due to the constancy of the cross section, negative influences on the seed trajectory are prevented.

In one embodiment of the invention, a section made of elastic material passes into adjacent sections of the material conduit without changes or almost without changes in the internal cross section. Shifts of components in the transition zone can significantly impede the passage of seeds. This is prevented by a transition with no or almost no offsets. Almost no displacement is defined as a transition where the displacement is less than 10% of the pipeline diameter.

In one embodiment of the invention, the section made of elastic material is at least partially made of fabric material. The pattern of the fabric may be, for example, cruciform, mesh or rhomboid. The fabric material increases the long-term strength of the section. In addition, the fabric maintains the elasticity of the section at a constant level throughout its life.

In one embodiment of the invention, the material conduit is flexible in at least one part. In this case, the flexible section may coincide with the elastic section or be located outside the elastic section. Thus, a non-elastic part of the material conduit, for example in an elbow, can additionally compensate for changes in the length of the material conduit resulting from changes in the length of the elastic section.

In one embodiment of the invention, the material conduit is flexible in at least one part in a bending plane parallel to the plane of movement of the metering unit to the machine frame. In this embodiment, the bending plane is vertical and directed along the direction of movement. Thus, in this embodiment, the bending occurs in a two-dimensional plane, and not in a three-dimensional space. Due to this, the effect of the lateral bending of the material pipeline, leading to eccentric placement of seeds in the furrow, is reduced or completely eliminated.

In one embodiment of the invention, a section of material conduit made of an elastic material is held taut at an average distance of the seed separator from the meter. Thus, for example, this section of material conduit can be stretched 25 mm relative to its unstressed length with a maximum allowable elasticity of 50 mm in this position of the separating device and meter. The section, made of elastic material, serves as a spring/damping element that acts on the movements of the seed separating tool. To pretension the hose section, it can be equipped, at least indirectly - directly or by means of a lever - with an energy store having the same or approximately the same effective spring rate as the hose section. In this way, a balance of forces is created by which the separating device is kept in a neutral position, from which it can move to an upper or lower end position.

In this prestressed position, the interior surfaces of this section of material conduit remain smooth and do not interfere with seed flow. There is no turbulence in the air flow used to deliver the seeds. Seeds cannot accumulate in material pipeline pockets. Preferably, the internal cross section is not reduced so much that the seed flow is impaired.

Another advantage of the elastic material in one of the sections of the material conduit is that the elastic section in the prestressed state is always located exactly along the predetermined feed direction. Due to the elastic vibrations of the material during the movements of the separating device and the metering unit, the seeds adhering to the inner wall of the section can be separated, so that it is not easily soiled or clogged.

In one embodiment of the invention, the separating device has at least one metering element for metering and separating seeds as a result of air pressure difference. This differential has the advantage of good seed acceleration and seed distribution in the seed separating tool. Separation accuracy in pneumatic systems is very high.

In one embodiment of the invention, there are elevations and (or) recesses on the inner surfaces of the material conduit, creating turbulence in the air flow near the walls. Turbulent flows create a kind of air cushion for seeds near the wall, which, as a result, are less decelerated due to friction against the inner walls of the material pipeline. As recesses, one can consider, for example, pits distributed over an area that create turbulent flows in the air flow. The air flow can be directed by the spoiler projections, creating turbulence and thus an air cushion for the seeds in the material pipeline.

In one embodiment of the invention, the half of the material conduit closest to the soil is connected to the movable opener support. The vertical movement of the coulter is transmitted by this connection to the material guide, so that when the coulter is displaced, the material guide is stretched and then contracted again. Thus, when the coulter moves vertically, the length of the material pipeline always corresponds to the required one.

In one of the embodiments of the invention, the device for separating seeds is connected to the metering unit with a spring and (or) a shock-absorbing element. This spring and/or shock absorber is designed to reduce the peak forces that can be applied to the material path during very fast or large movements of the seed separator and meter. It should be taken into account that, depending on the version of the seeder, the seed separating device is not only movably connected to the frame of the machine, but is also part of an assembly, for example, with a tank, which (especially when it is full) can exert significant forces when moving vertically while the planter is running. The sowing unit also has a large weight, which also exerts significant forces during vertical movements, which are transferred to the material pipeline. Due to the absence of a rigid connection, different amplitudes of movement of the device for separating seeds and the sowing device are reduced due to the spring and (or) the shock-absorbing element. This prolongs the life of the material line and also improves the performance of the separating device and the meter.

In one embodiment of the invention, the seed separating device is connected to the frame of the machine by a spring and/or a damping element. This also reduces the peak forces acting on the material conduit, since the spring and/or damping element smoothes the range of motion of the separating device or the assembly of which the device is part.

Other features of the invention are given in the claims, figures and description. All the signs and their combinations mentioned above in the description, as well as the signs and their combinations shown below in the figures and (or) in their descriptions, can be used not only in the indicated combinations, but also individually or in other combinations, if this is not prevented by any or technical reasons.

The invention is described in more detail based on the preferred embodiment with reference to the accompanying drawings.

The illustrations show:

fig. 1: seeder view,

fig. 2: side view of the material conduit with a telescopic section for changing the length of the material conduit between the separating device and the metering unit,

fig. 3 is an enlarged view of detail III of FIG. 2 - material conduit with a telescopic section and

fig. 4 Partially open side view of the movable connection between seed separator and meter

In FIG. 1 shows an oblique rear view of the seeder 2. The seeder 2 has a frame 4, to which several devices for separating seeds 6 are connected, each of which has one sowing machine 8. The sowing machines 8 consist of at least one coulter 10, one clamping element 12 and one material conduit 14, which directs the seeds separated in the device 6 through the outlet 16 into the groove. In the embodiment shown, the coulters 10 are double-disc coulters 32 arranged in a V-shaped position at an angle to each other, and their lower part plunges into the soil to open the furrow. The coulters 10 may be connected to a depth guide 18, which in this example is a wheel that follows the contour of the soil and runs close to the furrow. In the example shown, each depth guidance device 18 has one coulter 10 on both sides. In front of the coulters 10, there may additionally be compacting rollers 20 or other units for preparing the soil for sowing and fertilizing it before planting the seeds in the furrow. In this example, the rings of the packer rollers 20 form and compact grooves in the soil, in which the coulters 10 then form the final seeding furrows.

The device for separating seeds 6 is connected by levers 22 to the frame 4, and the sowing device 8 with the coulter 10 and the clamping element 12 is connected by levers 24 to the frame 4. coulter 10 and clamping element 12 can move vertically independently of each other so that the material pipeline 14 must pass different distances of length L, while the seeds must fall from the hole 16 to almost the same point on the clamping element 12.

The seed separating tool 6 has an inlet 7 for supplying seeds and/or creating an air pressure differential. A pressure differential is provided by a fan or compressor, not shown, to separate the seeds and make them easier to feed.

In FIG. 2 shows a side view of the material conduit 14 with a telescoping section 30 in which the tubular portions 26 fit into one another to adapt the length L of the material conduit 14 between the separating device 6 and the metering unit 8 depending on the needs.

The telescopic section 30 is located in the lower half of the material conduit 14, which is located between the seed separator 6 and the outlet 16 and has a length L. In the side view of the planter 2, this section is in the shade, that is, within the circumference of the disc coulter 32, which in In this example, it completely covers the telescoping section 30. The telescoping section 30 is mounted on a ski 34, which in this example is rigidly connected to the disc coulter 32. The outer of the two disc coulters 32 is not shown for clarity.

At the lower end of the material conduit 14 there is a curved section 36 in which the seeds deviate from the nearly vertical feed direction in the direction opposite to the direction of movement onto the pressing element 12.

Due to the air pressure difference, which is created by the inlet 7 in the seed separating device 6, the seeds are accelerated by the air flow and are fed from the seed separating device 6 to the material conduit 14.

In FIG. 3 in the section of the material conduit 14 in the area of the telescopic section 30 it is clearly seen that the tubular sections 26, 27 in section 30 can enter each other in the direction of the double arrow in the material conduit 14, and the ends of the tubular sections 26, 27 enter each other at different depths, as required depending on the respective length L of the material conduit 14. In this case, the lower part of the tube 27 is shaped so that it simultaneously forms a curved part 36.

As already shown in FIG. 1 and 2, in Fig. 4 shows two arms 24 vertically movable on frame 4 to move meter 8 relative to frame 4. Energy store 28—in this case a hydraulic cylinder—may apply a vertical force to the meter to improve furrow formation. Regardless of the sowing machine 8, the device for separating seeds 6 is also fixed on the frame 4 with two levers 22 that can be moved vertically. Between at least one arm 22 of the seed separator 6 and one arm 24 of the seed meter 8 are one or more springs/damping elements 40 which absorb and/or compensate for vibrations in the direction of the seed separator 6 that occur upon contact sowing machine 8 with soil. Alternatively or in addition to the embodiment shown, one or more springs/damping elements 40 may also be located directly between the seed separator 6 and the seed meter 8. The damping elements 40 are two leaf springs on one of the two arms 24; they slide until they stop corresponding to the respective levers 22, with the relative movement of the lever 22 to the lever 24, and deform accordingly. During deformation, a corresponding spring force arises, acting on the levers. The sliding motion results in a cushioning effect. The distribution of forces between the two levers 22 and 24 depends on the respective preload or spring rate. Instead of leaf springs, other flexural or coil springs, as well as hydraulic and/or pneumatic damping elements, can be used.

The invention is not limited to the above embodiments. The person skilled in the art will easily be able to adapt the presented options in a particular application.

List of positions

2 seeder

4 Machine frame

6 Seed Separator

7. Inlet

8 Seeding unit

10 Coulter

12 Pressure element

14 Material pipeline

16 Outlet

18 Depth guide

20 Packing roller

22 Lever (clamping element)

24 Lever (coulter)

26 Tubular section, telescopic

27 Tubular section, telescopic

28 Energy storage

30 Telescopic section

32 Disc coulter

34 Ski

36 Curved section

38 Stretch section

40 Spring or damping element

Claims (20)

1. An agricultural seeder (2) with a frame (4) and several sowing units (8) and devices for separating seeds (6) movably mounted on the frame (4), moreover, the sowing units (8) have at least one coulter (10 ), one material conduit (14) for supplying seed material from the separating device (6) to the planting area with an opening (16) located close to the soil, and one pressing element (12), while at least one coulter (10) , the hole (16) and the clamping element (12) are located in the sowing unit (8) in this working sequence, and the device for separating the seeds (6) without mechanically rigid connection is movably connected to the frame of the machine (4) using the corresponding device of the sowing unit ( 8), and the material conduit (14) consists of two tubular sections (26, 27), which can be pushed into each other telescopically in at least one section (30), characterized in that the sliding section (30) of the telescopic tubes ( 26, 27) is located at the bottom of the material conduit (14), moreover, the coulter (10) is one or two disc coulters (32), and the retractable section (30) of the telescopic tubes (26, 27) is - if you look at the seeder (2) from the side - completely inside the circle formed by one or more disc coulters (32), or partly in favor of it. 2. Seeder (2) according to claim 1, characterized in that on the outer side of the material conduit (14) in the area of the sliding section (30) of the telescopic tubes (26, 27) there is a cuff for sealing the telescopic connection. 3. Seeder (2) according to one of the previous paragraphs, characterized in that the retractable section (30) has at least one inner (26) and one outer part (27) of telescopic tubes (26, 27), and the outer part ( 27) is in the feed direction of the material conduit (14) after or below the inner part (26). 4. Seeder (2) according to one of the previous paragraphs, characterized in that having a retractable section (30) of telescopic tubes (26, 27) part of the material conduit (14) is connected to the supporting ski (34). 5. Seeder (2) according to claim 4, characterized in that the ski (34) is movably connected to the frame of the machine (4) so as to move relative to it. 6. Seeder (2) according to one of the preceding claims, characterized in that the bent section (36) of the material conduit (14) is connected to the retractable movable section (30) of the telescopic tube (26). 7. Seeder (2) according to one of the previous paragraphs, characterized in that the length of the material conduit (14) is changed due to the section (38) of the material conduit (14) made of elastic material, and the inner surface of the elastic section (38) is in the form of a hose. 8. Seeder (2) according to claim. 7, characterized in that the inner surface of the section (38), made of elastic material, has no folds and waviness. 9. Seeder (2) according to claim 7 or 8, characterized in that the section (38), made of elastic material, has a constant or almost constant internal cross-section along its entire length. 10. Seeder (2) according to one of paragraphs. 7-9, characterized in that the section (38), made of elastic material, passes into adjacent sections of the material conduit (14) without changes or almost without changes in the internal cross section. 11. Seeder (2) according to one of paragraphs. 7-10, characterized in that the section (38) made of an elastic material is at least partially made of a fabric material. 12. Seeder (2) according to one of the preceding claims, characterized in that the material conduit (14) is flexible in at least one part (36). 13. Seeder (2) according to claim 12, characterized in that the material conduit (14) is flexible in at least one section (30, 36) in the bending plane parallel to the plane of movement of the sowing unit (8) to the frame of the machine (4) . 14. Seeder (2) according to claim 13, characterized in that the section (38) of the material conduit (14) made of elastic material is preloaded in the tension direction in the installed state. 15. Seeder (2) according to one of the preceding claims, characterized in that the separating device (6) has at least one metering element for metering and separating the seeds as a result of the air pressure drop. 16. Seeder (2) according to one of paragraphs. 7-15, characterized in that on the inner surfaces of the material conduit (14) there are elevations and (or) depressions that create turbulence in the air flow near the walls. 17. Seeder (2) according to one of paragraphs. 7-16, characterized in that the half of the material conduit (14), closest to the soil, is connected to the opener movable support (10). 18. Seeder (2) according to one of paragraphs. 7-17, characterized in that the device for separating seeds (6) is connected to the sowing unit (8) by a spring and (or) a shock-absorbing element (40). 19. Seeder (2) according to one of paragraphs. 7-18, characterized in that the device for separating seeds (6) is connected to the frame of the machine (4) by a spring and (or) a damping element (40).

Images