Pneumatic conveying device for granular material and agricultural spreading machine

Abstract

The invention relates to a pneumatic conveyor device (4) for conveying granular material, in particular seeds and / or fertilizer, comprising at least one fan (5) with at least one outlet (10) connected to at least one main air supply line (11) into which an air volume flow (12) generated by a fan (5) flows, wherein the at least one main air supply line (11) opens into an air inlet (13) of an air distributing device (14) in order to control the air volume flow (12), wherein the air distributing device (14) has an even number of air outlets (15), each of which is connected to a connection line (L1, L2, L3,..., L8) connected to a metering device (16) for supplying the granular material, and the air distributing device (14) is designed as a cylindrical housing (17) with a rotary valve (18) arranged therein, said rotary valve being designed to change the outlet cross-section of the air outlets (15) in order to manipulate the supplied air volume flow (12) for transporting the granular material coming from the respective metering device (16).

Description

[0001] Description

[0002] Pneumatic conveying device for granular material and agricultural distribution machine

[0003] The present invention relates to a pneumatic conveying device for granular or particulate material, in particular seed and / or fertilizer, comprising at least one blower with at least one outlet, to which a main air supply line is connected, into which an air volume flow generated by the blower flows. The main air supply line opens into an air inlet of an air distribution device for controlling the air volume flow. The air distribution device has a plurality of air outlets, each of which is connected to a connecting line, to which a metering device for supplying the granular material is connected. Furthermore, the present invention relates to an agricultural distribution device.

[0004] Granular materials, for example in the form of seed or fertilizer, are typically transported from at least one storage container to one or more discharge units by means of a conveying device. Mechanical conveying devices or pneumatic conveying devices are used for this purpose. Pneumatic conveying devices convey the granular material by means of a blower through connecting lines from the storage container, for example, through a distribution device and a plurality of lines connected thereto, to the respective discharge units. The supply of the granular material from the at least one storage container to the conveying device is controlled by means of a metering device.

[0005] A pneumatic conveying device of the type mentioned above and an agricultural distribution device are known from US Pat. No. 4,779,765 A. An air volume flow generated by a blower is distributed between two air supply lines, each of which is used to transport granular material, which is fed to the respective air supply line by metering devices designed as metering rollers. The invention is based on the object of developing a pneumatic conveying device of the type mentioned above, which is characterized by flexible adjustment of the air flow rates supplied to the air outlets while simultaneously maintaining a compact design, particularly in the longitudinal direction of the distribution device.

[0006] This object is achieved by a pneumatic conveying device having the features of independent patent claim 1. Advantageous embodiments and further developments can be found in the dependent claims. Furthermore, the object is achieved by an agricultural distribution device according to claim 15.

[0007] According to claim 1, a pneumatic conveying device for conveying granular material, in particular seed and / or fertilizer, is proposed, comprising a blower with at least one outlet, to which at least one main air supply line is connected, into which an air volume flow generated by the blower flows, wherein the at least one main air supply line opens into an air inlet of an air distribution device for controlling the air volume flow, wherein the air distribution device has a preferably even number or a number divisible by three of air outlets, to each of which a connecting line is connected, to which a metering device for supplying the granular material is connected.According to the invention, the air distribution device is designed as a cylindrical housing with a rotary slide valve arranged therein, which is designed to change an outlet cross-section of the air outlets in order to manipulate the supplied air volume flow for the transport of the granular material coming from the respective dosing device.

[0008] The invention is based on the idea of ​​being able to adapt the air volume flow to different operating situations. In particular, a compact design can be achieved by integrating the rotary valve, which is designed to change the outlet cross-section of the, in particular, essentially circular, air outlets, into the housing. Furthermore, the rotary valve enables a targeted distribution of the air volume flow to the air outlets, ranging from a complete supply of all air outlets to a supply of the air volume flow limited to half or one-third of the air outlets. Various intermediate divisions into partial air flows are possible. Preferably, an actuator can be arranged on the rotary valve, by means of which the rotary valve can be operated manually or automatically.The actuator can, for example, be designed as an electric motor that can be used to change the position of the rotary valve relative to the air outlets. Alternatively, the actuator can be designed as a lever that can be operated manually by an operator.

[0009] In particular, the rotary valve can be designed as an arcuate section which can be pivoted about a longitudinal axis of the housing and which has recesses which extend in sections in the circumferential direction of the arcuate section and which interact with the air outlets of the housing depending on a set pivot position of the arcuate section. The arcuate section is arranged concentrically to the longitudinal axis of the housing so that the longitudinal axis is also the pivot axis of the rotary valve. By pivoting the arcuate section, the recesses can be adjusted relative to the air outlets in such a way that all air outlets are completely exposed, i.e. the recesses completely cover the respective air outlet up to a partial coverage of half the number of air outlets by the outer surface of the rotary valve.In the first case of complete overlap, the air flow supplied by the fan is distributed essentially evenly across all air outlets. In the case of only partial overlap, the ratio of the distribution of the supplied air flow can be varied depending on the set pivot angle of the curved section around its pivot axis, which runs coaxially with the longitudinal axis of the housing.

[0010] Preferably, the rotary valve can be adjusted in discrete steps or continuously. Adjusting the rotary valve in discrete steps has the advantage that predefined ratios for the distribution of the supplied air volume flow to the air outlets can be set. Continuous adjustment of the rotary valve enables more precise adjustment of the distribution of the supplied air volume flow to the air outlets. To adjust the ratio of the distribution of the supplied air volume flow in discrete steps, the actuator, designed as a lever, can be locked in detent positions on the housing. A locking device can be provided for this purpose. Alternatively, the electric motor can be designed as a stepper motor, which also allows the ratio to be adjusted in discrete steps.

[0011] Preferably, the housing can have a circular-cylindrical shape, thereby achieving a more compact design of the air distribution device. In particular, the housing is arranged transversely to the main air supply line and the connecting lines connected to the air outlets, which, at least in sections, run essentially in a common direction. This arrangement of the housing, which runs transversely to the connecting lines, has the advantage of providing more installation space for the dosing devices.

[0012] Further preferably, the recesses can have an extension in the circumferential direction of the section which corresponds to at least twice the diameter of the outlet cross-section of the air outlets.

[0013] Furthermore, the recesses can have a width in the axial direction that is at least equal to or less than the diameter of the outlet cross-section of the air outlets. By reducing some of the outlet cross-sections of the recesses, less severe or different flow resistances in downstream lines of different lengths can be compensated for, for example.

[0014] In a particular embodiment, the recesses near a main air supply duct can have a smaller opening cross-section or a smaller width than recesses farther away from the main air supply duct. This embodiment reduces increased air flows, such as those that occur in the vicinity of the main air supply duct, to achieve a more uniform air flow in all air outlets.

[0015] In particular, the recesses can have a substantially elliptical opening cross-section. An elliptical opening cross-section is understood to mean, in particular, those that have a different width and extension along the circumferential direction, such as an elongated hole.

[0016] Preferably, the recesses can be arranged with an alternating offset in the circumferential direction of the rotary valve. The opening cross-sections of two immediately adjacent recesses have a common overlap area in the circumferential direction.

[0017] According to a preferred development, the air outlets can be arranged next to one another on the housing, axially parallel to the longitudinal axis of the housing. This simplifies the attachment and routing of the connecting lines. This also simplifies the connection of the dosing devices to the connecting lines. In particular, the at least one main air supply line can be arranged opposite the air outlets on the housing or coaxially to the housing. The main air supply line and the connecting lines arranged at the air outlets can thus be arranged in sections in a common plane, which also has a positive effect on the installation space requirement of the pneumatic conveying device. The main air supply line can be arranged symmetrically or asymmetrically on the housing with respect to the center of the housing.A coaxial connection of the main air supply line to one end of the housing is particularly advantageous if the housing also forms a, preferably load-bearing, component of a machine frame.

[0018] According to a further development, the air outlets can be arranged in pairs next to each other or in a group of three, wherein the distance between the air outlets of at least one pair or group of three is smaller than the distance to an adjacent pair or group of air outlets. A group-wise arrangement of lines and thus their associated air outlets is advantageous, particularly for dosing devices arranged in cascade.

[0019] In particular, each pair of air outlets can be followed by two of the dosing devices in the conveying direction, wherein both dosing devices can be connected to both connecting lines assigned to the respective air outlets in order to selectively supply the material of one dosing device or of both dosing devices to one connecting line or both connecting lines.

[0020] For this purpose, each dosing device can have a switching element that can be operated manually or by an actuator, which connects or disconnects the respective dosing device to one or both connecting lines. For example, the dosing devices can have switching elements designed as switching flaps, which allow the material to be alternately fed to only one of the connecting lines or to both connecting lines. The dosing devices, in turn, are designed to be switchable, so that all connecting lines can be supplied with material from only half of the dosing devices.

[0021] Furthermore, the object posed at the outset is achieved by an agricultural distribution machine for conveying granular material taken from at least one storage container, comprising a pneumatic conveying device, which is designed according to one of claims 1 to 14. Reference is made to all statements regarding the proposed pneumatic conveying device. The present invention is explained in more detail below with reference to an exemplary embodiment illustrated in the drawings.

[0022] They show:

[0023] Fig. 1 is a schematic representation of a tractor and an agricultural distribution machine;

[0024] Fig. 2 is a partial view of a pneumatic conveying device;

[0025] Fig. 3 is a partial perspective view of the pneumatic conveying device according to Fig. 2;

[0026] Fig. 4 is a perspective view of an air distribution device;

[0027] Fig. 5 is a schematic partial sectional view of the air distribution device according to Fig. 4 in a first exemplary switching position;

[0028] Fig. 6 is a schematic partial sectional view of the air distribution device according to Fig. 4 in a second exemplary switching position;

[0029] Fig. 7 is a schematic partial sectional view of the air distribution device according to Fig. 4 in a third exemplary switching position; and

[0030] Fig. 8 is a schematic partial sectional view of the air distribution device according to Fig. 4 in a fourth exemplary switching position.

[0031] Fig. 1 shows a schematic representation of a towing vehicle 1, in particular a tractor, and an agricultural spreading machine 2 arranged thereon. The towing vehicle 1 serves to move the spreading machine 2 over an area to be worked in one direction of travel and to supply it with drive energy. Two supply lines 3 are shown purely as an example, which serve to provide a hydraulic fluid and / or electrical energy for driving a fan 5, in particular a hydraulically driven fan, of a pneumatic conveying device 4 of the spreading device 2. The spreading machine 2 has a storage container 6, which is divided into two segments 6a, 6b by a partition wall 7. Alternatively, two separate storage containers 6 can be provided. The storage container 6 contains granular material, in particular seed and / or fertilizer, which is spread by the spreading machine 2.The granular material is conveyed by the pneumatic conveying device 4 to discharge units 8, 9, which introduce the granular material into the soil. Each discharge unit 8 may have one or more seed coulters, and each discharge unit 9 may have one or more fertilizer coulters. An even number or a number divisible by three of discharge units 8, 9 is provided.

[0032] The blower 5 is provided with at least one outlet 10, to which at least one main air supply line 11 is connected, into which an air volume flow 12 generated by the blower 5 flows. The at least one main air supply line 11 opens into an air inlet 13 of an air distribution device 14 for dividing the air volume flow 12. The air distribution device 14 has an even number of air outlets, to each of which a connecting line L1, L2, ..., L8 is connected.

[0033] From the individual segments 6a, 6b of the storage container 6, the granular material is fed to the individual connecting lines L1, L2, ..., L8 of the conveying device 4 by means of dosing devices 16. The dosing devices 16 precisely dose the amount of material to be conveyed from the conveying device 4 to delivery units 8, 9. The dosing devices 16 are arranged below the storage container 6, between the storage container 6 and the connecting lines L1, L2, ..., L8 of the conveying device 4. According to the agricultural distribution machine 2 shown in Fig. 1, the granular material is fed from the respective segment 6a, 6b of the storage container 6 to the respective dosing device 16 essentially by gravity. The dosing devices 16 can be divided into two or more groups G1, G2, each group G1, G2 having half the number of connecting lines L1, L2, ..., L8 corresponding number of metering devices 16. The group G1 with metering devices 16 is arranged directly behind the air distribution device 14. The group G2 with metering devices 16 is arranged downstream of these, as seen in the conveying direction FR of the granular material.

[0034] The connecting lines L1, L3, L5, and L7 can be assigned to group G2, to which the seed to be pneumatically conveyed is supplied by the metering devices 16 of group G2. The connecting lines L2, L4, L6, and L8 can be assigned to group G1, to which the fertilizer to be pneumatically conveyed is supplied by the metering devices 16 of group G1. Fig. 2 shows a partial view of the pneumatic conveying device 4 in a view from above. The illustration in Fig. 3 shows a perspective partial view of the pneumatic conveying device 4 according to Fig. 2.

[0035] The air distribution device 14 comprises a cylindrical housing 17. The housing 17 of the air distribution device 14 is arranged transversely to the main air supply line 11 and the connecting lines L1, L2, ..., L8 connected to the air outlets 15, which at least partially run essentially in a common direction, and which run transversely to these lines. The connecting lines L1, L2, ..., L8 run partially in the longitudinal direction of the distribution machine 2. The housing 17 preferably has a circular cylindrical shape. The arrangement of the air distribution device 14 oriented transversely to the longitudinal axis of the distribution machine 2 enables a space-optimized arrangement of this and other components of the pneumatic conveying device 4, such as the blower 5, which is particularly clear from Fig. 1.

[0036] The illustration in Fig. 4 shows a perspective view of the air distribution device 14. The air distribution device 14 is designed as the cylindrical housing 17 with a rotary valve 20 arranged therein, as explained in more detail in the following Figs. 5 to 8. The rotary valve 18 arranged in the housing 17 is configured to change an outlet cross-section of the air outlets 15 in order to manipulate the supplied air volume flow 12 for the transport of the granular material coming from the respective dosing device 16. To actuate the rotary valve 18, an actuator designed as a lever 19 is pivotally attached to the rotary valve 18 about a pivot axis 21 coaxial with the longitudinal axis 20 of the housing 17. To fix the rotary valve 18 in a defined position, an annular segment-shaped section 22 is arranged on the outside of the housing 17 adjacent to the lever 19.The ring-segment-shaped section 22 has recesses 23 extending radially relative to the pivot axis 21, for example in the form of elongated holes. A locking lug (not shown) is arranged at the free end of the lever 19, which can be engaged with one of the recesses 23 to position the rotary valve 18 in a desired position. Depending on the position of the lever 19 or the rotary valve 18, the air volume flow 12 is divided into partial volume flows 28, 29, which will be explained in more detail below.

[0037] Fig. 5 shows a schematic partial sectional view of the air distribution device 14 according to Fig. 4 in a first switching position of the rotary slide 18. The rotary slide 18 is designed as a circular arc-shaped section 24 that can be pivoted about the longitudinal axis 20 of the housing 17. Both the housing 17 and the rotary slide 18 or its circular arc-shaped or cylinder segment-shaped section can also be designed as a polygonally folded sheet metal blank. The number of folds, like a polygon, approximates a circle as closely as possible. The circular arc-shaped section 24 has recesses 25 extending in sections in the circumferential direction of the section 24, which interact with the air outlets 15 of the housing 17 depending on the set position, i.e. the pivot angle set by the actuator, of the arc-shaped section 24.In the axial direction, at least one circular sector-shaped section 26 is arranged at the end of the circular arc-shaped section 24. The circular arc-shaped section 24 is pivotally mounted on the housing 17 of the air distribution device 14 by means of the circular sector-shaped section 26. The lever 19 engages one of the two circular sector-shaped sections 26 in a rotationally fixed manner in order to pivot the lever 19 together with the circular arc-shaped section 24 about the pivot axis 21 in the pivot direction 27.

[0038] 4 to 8, the rotary slide valve 18 can be adjusted in discrete steps in the pivoting direction 27, in particular manually. The step size, i.e. the distance between the recesses 23 in the circumferential direction, determines the ratio of the distribution of the supplied air volume flow 12. Alternatively, the rotary slide valve 18 can be continuously adjustable. For this purpose, an actuator designed as an electric motor, for example, can be arranged on one of the circular sector-shaped sections 26. In particular, the actuator designed as an electric motor can bring about automatic adjustment. For example, a control command can be generated by a control unit of the towing vehicle 1 or the distribution machine 2, which control command is used to control the actuator in order to set a pivoting angle which corresponds to a ratio of the division of the air volume flow 12 into the partial volume flows 28, 29, specified by an operator.

[0039] The recesses 25 have an extension L in the circumferential direction of the circular-arc section 24, which corresponds to at least twice the diameter D of the outlet cross-section of the air outlets 15. The recesses 25 have a width B in the axial direction, which corresponds at least to the diameter D of the outlet cross-section of the air outlets 25. Preferably, the recesses 25 have a substantially elliptical opening cross-section.

[0040] The recesses 25 are arranged with an alternating offset in the circumferential direction of the rotary valve 18 or the circular-arc section 24, as seen in the circumferential direction. The air outlets 15 are arranged next to one another on the housing 17, parallel to the longitudinal axis 20 thereof. The air outlets 15 are arranged next to one another in pairs, wherein the distance between the air outlets 15 of a pair can be smaller than the distance to an adjacent pair of air outlets 15. In the illustrated embodiment, four air outlets 15, with connecting lines L8, L7, L6, L5 arranged thereon, are arranged in groups with the same axial distance from one another. The other four air outlets 15, with connecting lines L1, L2, L3, L4 arranged thereon, are also arranged in groups with the same axial distance from one another.There is a greater axial distance between the central air outlets 15, at which the connecting lines L5 and L3 are arranged. In addition, the air outlets 15 with the connecting lines L8, L7, L6, L5 can be arranged mirror-symmetrically to the air outlets 15 with the connecting lines L1, L2, L3, L4. This offers advantages when laying the hoses. Each pair of air outlets 15 is assigned two correspondingly arranged recesses 25 in the circular arc-shaped section 24, wherein the recesses 25 extend in opposite directions viewed in the circumferential direction, i.e. are arranged offset from one another. Any two recesses 25 assigned to a pair of air outlets 15 have a common overlap region in which both air outlets 15 of a pair are fully exposed, as can be seen from Fig. 5.

[0041] In Fig. 5, the division of the air volume flow 12 into two proportional partial volume flows 28 and 29 by the rotary slide 18 is shown for a pair of air outlets 15, representative of all paired air outlets 15. The lever 19 is in a central position in which all air outlets 15 are completely open through the recesses 25. Accordingly, the supplied air volume flow 12 is distributed evenly among all air outlets 15, with each of the connecting lines L1, L3, L5 and L7 as well as L2, L4, L6 and L8 being supplied with equal partial volume flows 28 for fertilizer and partial volume flows 29 for seed. With respect to the paired air outlets 15, the air volume flow 12 is divided in a ratio of essentially 50:50.

[0042] The illustration in Fig. 6 shows a schematic partial sectional view of the air distribution device 14 according to Fig. 4 in a second exemplary switching position. As can be seen from the position of the lever 19, the rotary slide 18 has been moved in a pivoting direction 27, in which the air outlets 15, to which the connecting lines L1, L3, L5 and L7 are connected, are essentially covered by the outer surface of the rotary slide 18, while the air outlets 15, to which the connecting lines L2, L4, L and L8 are connected, remain completely open. With respect to the paired air outlets 15, the air volume flow 12 is divided into the respective partial flows 28 and 29 in a ratio of approximately 90:10.

[0043] Fig. 7 shows a schematic partial sectional view of the air distribution device according to Fig. 4 in a third exemplary switching position. As can be seen from the position of the lever 19, the rotary slide 18 has been moved in a pivoting direction 27 in which the air outlets 15, to which the connecting lines L1, L3, L5 and L7 are connected, remain completely open, while the air outlets 15, to which the connecting lines L2, L4, L and L8 are connected, are partially covered by the outer surface of the rotary slide 18. With respect to the paired air outlets 15, the air volume flow 12 is divided into the respective partial flows 28 and 29 in a ratio of approximately 30:70.

[0044] The illustration in Fig. 8 shows a schematic partial sectional view of the air distribution device 14 according to Fig. 4 in a fourth exemplary switching position. As can be seen from the position of the lever 19, the rotary slide valve 18 has been moved in a pivoting direction 27, in which the air outlets 15, to which the connecting lines L2, L4, L6, and L7 are connected, are essentially covered by the outer surface of the rotary slide valve 18, while the air outlets 15, to which the connecting lines L1, L3, L5, and L7 are connected, remain completely open. With respect to the paired air outlets 15, the air volume flow 12 is divided into the respective partial flows 28 and 29 in a ratio of approximately 10:90.

[0045] As already explained above, the exemplary adjustment options in Figs. 5 to 8 were described based on the adjustment of the actuator, designed as a lever 19, in the pivoting direction 27, carried out in discrete steps around the pivot axis 21. Continuous adjustment by means of an actuator designed as an electric motor is also conceivable, which, in addition to automating the adjustment or setting, can achieve a finer gradation of the distribution of the respective partial flows 28 and 29. List of reference symbols

[0046] 1 towing vehicle 28 partial volume flow

[0047] 2 Distributor 29 Partial volume flow

[0048] 3 Supply line B width of 25

[0049] 4 Conveyor D diameter of 15

[0050] 5 Blower L extension of 25

[0051] 6 Storage container FR conveying direction

[0052] 6a Segment G1 Group

[0053] 6b Segment G2 Group

[0054] 7 Partition L1 connecting line

[0055] 8 Delivery unit L2 connecting line

[0056] 9 Dispensing unit L3 connecting line

[0057] 10 Outlet L4 connecting line

[0058] 11 Main air supply line L5 Connection line

[0059] 12 Air volume flow L6 connecting line

[0060] 13 Air inlet L7 connecting line

[0061] 14 Air distribution device L8 connecting line

[0062] 15 Air outlet

[0063] 16 Dosing device

[0064] 17 housings

[0065] 18 rotary valves

[0066] 19 levers

[0067] 20 Longitudinal axis

[0068] 21 Swivel axis

[0069] 22 Ring segment-shaped section

[0070] 23 Recess

[0071] 24 Arched section

[0072] 25 recess

[0073] 26 Circular sector-shaped section

[0074] 27 Panning direction

Claims

Patent claims 1. Pneumatic conveying device (4) for conveying granular or granular material, in particular seeds and / or fertilizer, comprising at least one blower (5) with at least one outlet (10) to which at least one main air supply line (11) is connected, into which an air volume flow (12) generated by the blower (5) flows, wherein the at least one main air supply line (11) opens into an air inlet (13) of an air distribution device (14) for controlling the air volume flow (12), wherein the air distribution device (14) has an even number or a number divisible by three of air outlets (15), to each of which a connecting line (L1, L2, L3, ...) is connected., L8) is connected to which a metering device (16) for supplying the granular material is connected, characterized in that the air distribution device (14) is designed as a cylindrical housing (17) with a rotary slide (18) arranged therein, which is designed to change an outlet cross-section of the air outlets (15) in order to manipulate the supplied air volume flow (12) for the transport of the granular material coming from the respective metering device (16).

2. Pneumatic conveying device (4) according to claim 1, characterized in that an actuator (19) is arranged on the rotary valve (18) by which the rotary valve (18) can be actuated manually or automatically.

3. Pneumatic conveying device (4) according to claim 1 or 2, characterized in that the rotary slide (18) is designed as an arc-shaped section (24) pivotable about a longitudinal axis (20) of the housing (17), which has recesses (25) extending section by section in the circumferential direction of the section (24), which interact with the air outlets (15) of the housing (17) depending on a set pivot position of the arc-shaped section (24).

4. Pneumatic conveying device (4) according to one of claims 1 to 3, characterized in that the rotary slide (18) is adjustable in discrete steps or continuously.

5. Pneumatic conveying device (4) according to one of the preceding claims, characterized in that the housing (17) has a circular cylindrical shape.

6. Pneumatic conveying device (4) according to one of claims 3 to 5, characterized in that the recesses (25) in the circumferential direction of the section (24) have an extent (L) which corresponds at least to twice the diameter (D) of the outlet cross-section of the air outlets (15).

7. Pneumatic conveying device (4) according to one of claims 3 to 6, characterized in that the recesses (25) have a width (B) in the axial direction which at least corresponds to or is less than the diameter (D) of the outlet cross-section of the air outlets (15).

8. Pneumatic conveying device (4) according to one of claims 3 to 7, characterized in that the recesses (25) in the vicinity of a main air supply line (11) have a smaller opening cross-section or a smaller width (B) than recesses (25) located further away from the main air supply line (11).

9. Pneumatic conveying device (4) according to one of claims 3 to 7, characterized in that the recesses (25) have a substantially elliptical opening cross-section.

10. Pneumatic conveying device (4) according to one of claims 3 to 8, characterized in that the recesses (25) are arranged with an alternating circumferential offset to each other when viewed in the circumferential direction of the rotary slide (18).

11. Pneumatic conveying device (4) according to one of claims 1 to 9, characterized in that the air outlets (15) are arranged side by side on the housing (17) parallel to the longitudinal axis (20).

12. Pneumatic conveying device (4) according to claim 10, characterized in that the at least one main air supply line (11) is arranged opposite the air outlets (15) on the housing (17) or coaxially to the housing (17).

13. Pneumatic conveying device (4) according to claim 10 or 11, characterized in that the air outlets (15) are arranged in pairs next to each other or in a group of three, wherein the distance between the air outlets (15) of at least one pair or group is less than the distance to an adjacent pair or a group of air outlets (15). Pneumatic conveying device (4) according to claim 12, characterized in that each pair of air outlets (15) is followed by two metering devices (16) in the conveying direction (FR), wherein both metering devices (16) can be connected to both connecting lines (L1, L2, L3, ..., L8) associated with the respective air outlets (15) in order to selectively supply the material of one metering device (16) or of both metering devices (16) to one connecting line (L1, L2, L3, ..., L8) or to both connecting lines (L1, L2, L3, ..., L8). Pneumatic conveying device (4) according to claim 13, characterized in that each dosing device (16) has a switching element that can be operated manually or by an actuator, which connects or disconnects the respective dosing device (16) from one or both connecting lines (L1 , L2, L3, ... , L8).Agricultural distribution machine (2) for conveying granular material taken from at least one storage container (6) with a pneumatic conveying device (4) according to one of claims 1 to 14.