Output unit comprising a feed device, an agricultural implement with such an output unit and a method for controlling flow in the agricultural implement

Abstract

32ABSTRACTA feed device (145) for feeding granular material from an agricultural implement for distributing said granular material to ground over which the agricultural implement travels comprises a device housing (1450), a material inlet (1451), for receiving said granular material in the device housing, a material outlet (1452), for delivering said granular material from the device housing; and a transfer device (1455, 1456) configured for transporting said granular material to the material outlet. The transfer device (1455, 1456) comprises an auger conveyor (1456), which is configured to elevate said granular material to the material outlet (1452).(Fig. 4)

Description

FEED DEVICE. OUTPUT DEVICE. AGRICULTURAL IMPLEMENT AND METHOD OF FEED GRANULAR MATERIAL IN AN AGRICULTURAL IMPLEMENTTechnical fieldThe present disclosure relates to a feed device for singulation and / or flow control of granular material, such as seeds, fertilizer or pesticide, in an output unit of an agricultural implement for distributing granular material to ground over which the agricultural implement travels.The disclosure further relates to a method of feeding granular material from an agricultural implement.The disclosure finds utility in the feeding, or flow regulation, of seeds near a delivery point in a volumetrically operated seeder, which is typically used for drill seeding of crops such as wheat, barley and other small grain seeds.The disclosure also finds utility in connection with so-called "central fill" systems, which would normally be provided for feeding seeds from a central container to a plurality of feed devices in a planter.BackgroundDevices for singulating granular material, in particular seeds, are known for use in agricultural implements such as planters (also known as "precision planters") and seeders (aka "drill seeders" or "seed drills").In planters, the singulating device is used for lining up individual seeds to be placed at predetermined distances from each other. Such planters are disclosed in e.g. W02011119095A1 and WO2022182279A1.In seeders, singulating devices can be used in order to control the flow of seeds from each output unit, such that a predetermined and uniform flow of seeds is achieved, which can be regulated based on e.g. the ground speed of the implement or of the individual output unit, such that a more precise amount of seeds per area can be provided as compared with the use of a central seed meter, the output of which is distributed to a plurality of output units. WO2015069179A1 discloses such an agricultural implement.WO2023282830A1 discloses the idea of using a singulating device of the type normally used for planters for controlling the flow of seeds in a drill seeder.However, there remains a need for an improved feed device, in particular for drill seeders. It is particularly desirable to provide a feed device which is compact and reliable, while providing an even, and preferably controllable, flow of seeds, also during such harsh conditions as may occur when an agricultural implement is drawn at speed over uneven ground.SummaryIt is an objective of the present disclosure to provide an improved feed device. Particular objectives include the provision of a feed device, which is compact and reliable and which provides an even, and preferably controllable, flow of seeds. A further objective is to provide a feed device which can be produced at a low cost. A yet further objective is to provide a feed device which can be adapted for use with different sorts of materials, such as different sorts of seeds.The invention is defined by the appended independent claims, with embodiments being set forth in the appended dependent claims, in the following description and in the attached drawings.According to a first aspect, there is provided a feed device for feeding granular material from an agricultural implement for distributing said granular material to ground over which the agricultural implement travels, comprising a device housing, a material inlet, for receiving said granular material in the device housing, a material outlet, for delivering said granular material from the device housing; and a transfer device configured for transporting said granular material to the material outlet. The transfer device comprises an auger conveyor, which is configured to elevate said granular material to the material outlet.The feed device may, in some implementations, operate as a singulating device, and in others as a flow tuning device or a flow equalization device.The transfer device being "configured to elevate" implies that the material is lifted from a lower vertical level at an inlet of the transfer device to a higher vertical level at an outlet of the transfer device.At the material outlet, the granular material may be caused to fall by gravity into a chute connecting to a delivery tube. Alternatively, the granular material may be taken up by an airflow, which may convey the material to, and optionally through, a delivery tube.In some embodiments, the material outlet may connect directly to a relatively short seed tube, such that a delivery point may be fixed in relation to the feed device.A device as defined above can be produced with relatively few moving parts, all of which can be made robust and can be produced at a low cost. Moreover, the device may reduce the need dynamic seals, which simplifies its construction. The transfer device can be controlled by an electric motor, which may be a continuously drivable motor or a stepper motor.By elevating the granular material to the material outlet, effects of agitation (shaking) of the agricultural implement can be mitigated, as can the risk of pulsations in the feeding of the granular material, since the gravitation will operate to counteract the outputting of the material and to keep a constant fill level along the auger.Another advantage is that, when stopping the auger, a more immediate stopping of the feeding of the granular material is achieved.The auger conveyor may present an axis of rotation, which, when the feed device is in an operating position, presents an angle to a vertical direction, which is about 0-45 degs, preferably about 0-40 degs, about 0-30 degs, about 0-20 degs, about 0-10 degs, about 0-5 degs or about 0-1 deg.The auger conveyor may comprise a helical blade having a blade pitch, and the helical blade may present at least two portions which are spaced apart along an axis of rotation and which present different blade pitches.The blade may be continuous. In some embodiments, the variation in blade pitch may occur continuously over the length of all or a part of the helical blade. In other embodiments, the variation in blade pitch may occur stepwise, e.g. such that the helical blade presets two or more portions with different constant blade pitches.A blade section which is closer to the material outlet may present a smaller blade pitch than a blade section which is further away from the material outlet.Alternatively, a blade portion which is closer to the material outlet may present a greater blade pitch than a blade portion which is further away from the material outlet.The auger conveyor may, along at least a portion of its length, be devoid of auger axle.The auger conveyor may comprise an auger axle, and the auger axle may present at least two portions which are spaced apart along a axis of rotation and which present different axle thicknesses.Hence, it is possible to control displacement of the auger conveyor.The axle diameter may vary continuously over all or part of the axle.Alternatively, the axle may be divided into two or more portions, each having a fixed axle diameter.A blade outer diameter may vary along the axis of rotation, such that a displacement of the helical screw varies along the axis of rotation.At least a portion of the blade may present enhanced surface friction.At least a portion of the blade may present surface variations for engaging granules.Surface variations may be e.g. grooves, ridges, holes or the like which may support granules.The screw blade may present a plurality of recesses or through holes configured for receiving granules of said granular material.The screw blade may present a plurality of generally radially extending grooves and / or ridges configured for receiving granules of said granular material.The device housing may enclose a material buffer, which is configured to hold an amount of said granular material, and the transfer device may be configured to elevate the granular material from the material buffer to the material outlet.The feed device may further comprise a drive unit, operatively connected to the transfer device, for driving the transfer device.The feed device may further comprise a granule sensor, configured to detect granules exiting through the material outlet, and a controller, configured to control the operation of the drive unit based, at least partially, on a signal from the granule sensor.The drive unit may comprise a drive unit housing, which may be arranged below the device housing.Alternatively, the drive unit may comprise a drive unit housing, which is arranged above the device housing.The drive unit may be operatively connected to at least two transfer devices. For example, two or more transfer devices may be connected by a transmission device, such as a gear, belt or chain arrangement.In some embodiments, such a feed device may be provided on a row unit configured to deliver granular material to two or more rows.In other embodiments, such a feed device may be arranged at a central container, corresponding to a central fill system, where the material outlets are connected to tubes or hoses for transport to respective delivery points.The at least two transfer devices may be configured to feed material from a single material inlet.Hence, the transfer devices may be configured to feed material from the same material container or material buffer, but to different material outlets and for distribution by different delivery tubes.The feed device may further comprise a material takeup section provided at an uppermost portion of the transfer device and an airflow inlet connecting to the material takeup section, whereby the material takeup section may be configured such that material transferred to the material takeup section is picked up by an airflow provided through the airflow inlet and provided as a material-laden airflow to the material outlet.Hence, the granular material may be conveyed from the material outlet by means of an airflow.By using an airflow, the precision is increased and sensitivity to agitation (shaking) of the implement is decreased, as compared to a feed device using only gravity to transport the material towards the delivery point.The material outlet may be concentric with the transfer device.The material outlet may be connected to a delivery tube.The delivery tube may provide a delivery point for the granular material, or it may connect to a seed boot or a seed knife.The feed device may further comprise an auger screw load limiting arrangement.The auger screw may be axially displaceable for limiting its immersion into the granular material.The transfer device may connect to an air channel, configured for conveying the granular material to the material outlet by means of an airflow.The feed device may further comprise a constriction of said air channel at a transfer device outlet. This increases the air velocity at the device outlet, which may facilitate the insertion of the granular material into the airflow.The air channel may extend substantially horizontally at the material outlet.The air channel may be configured to provide an airflow which is directed along a material flow direction in the transfer device.The air channel may be configured to provide an airflow which is directed opposite a material flow direction in the transfer device.The air channel may at least partially surround an auger housing of the transfer device.The feed device may further comprise an airflow deflector, positioned upstream of a transfer device outlet, as seen relative to the airflow.According to a second aspect, there is provided an output unit for an agricultural implement, comprising a furrow opener, a delivery tube, having a tube inlet and a tube outlet configured to guide material into a furrow opened by the furrow opener, and a feed device as claimed in any one of the preceding claims, wherein the material outlet of the feed device is connected to the tube inlet.The furrow opener, the delivery tube and optionally the feed device may all be mounted on a common output unit frame, which may be movably mounted to an implement frame. Alternatively, the feed device may be mounted on an implement frame, with the furrow opener mounted on an output unit frame and the feed tube connecting, optionally flexibly, the feed device to the furrow opener.According to a third aspect, there is provided an agricultural implement for distributing granular material to ground over which the agricultural implement travels, comprising a plurality of output units as described above.The agricultural implement may be a seeder, a planter, or the like, with each of the output units being configured to feed granular material from the agricultural implement to the ground, granueThe agricultural implement may further comprise a central material container and a feed arrangement for feeding material from the central container to at least some of the output units.In the agricultural implement, the feed arrangement may comprise one or more primary material feed lines for pneumatically guiding material from the central container.In the agricultural implement, each of the primary material feed lines may be connected directly to a respective one of the output units.In the agricultural implement, the feed arrangement may comprise at least one distributor having a distributor inlet which is connected to a primary material feed line and at least two distributor outlets, which are connected via secondary material feed lines to a respective one of the output units.According to a fourth aspect, there is provided a method of controlling flow of a first granular material in an agricultural implement, comprising feeding a respective flow of said first granular material to a plurality of output units of the agricultural implement, and at each of said output units: receiving the flow of said first granular material in a feed device, transferring said first granular material upwardly towards a material outlet using an auger conveyer, and guiding said first granular material from the material outlet towards ground to which the material is to be deposited.The guiding may be performed at least partially by means of an airflow.The method may further comprise constricting said airflow in order to increase a velocity thereof at a position where said granular material transported by said auger conveyer merges with said airflow, in order to achieve a more reliable material pickup.The method may further comprise providing a second granular material and guiding said second granular material together with said first granular material.The auger conveyor may comprise an auger screw and the method may comprise limiting a loading of an auger screw by immersing it into the granular material present in the device housing by less than about 250 % of a turn of a screw blade, preferably about 200-250 %, about 150-200 %, about 100-150 %, about 75-100 %, about 50-75 %, about 25-50 % or about 5-25 %.DrawingsFig. 1 is a schematic side view of an agricultural implement 1 connected to a traction vehicle 2.Fig. 2 is a schematic side view of an agricultural implement 1 connected to a traction vehicle 2.Fig. 3 is a schematic side view of an output unit 140.Fig. 4 is a schematic illustration of a first embodiment of a feed device.Fig. 5 schematically illustrates the extent of the auger axis and its angle to the vertical direction.Fig. 6 is a schematic illustration of a second embodiment of a feed device. Fig. 7 is a schematic illustration of a feed device provided with a granule sensor.Fig. 8 is a schematic illustration of a feed device provided with an auger having varying blade pitch.Fig. 9 schematically illustrates a feed device feeding seeds into a combination seed channel.Figs 10a-10b schematically illustrate different degrees of immersion of the auger screw into the granular material.Fig. 11 schematically illustrates the configuration of the material takeup section according to a first design thereof.Fig. 12 schematically illustrates the configuration of the material takeup section according to a second design thereof.Fig. 13 schematically illustrates the configuration of the material takeup section according to a third design thereof.Fig. 14 schematically illustrates the configuration of the material takeup section according to a fourth design thereof.Fig. 15 schematically illustrates the configuration of the material takeup section according to a fifth design thereof.Fig. 16 schematically illustrates a first design of the auger screw.Fig. 17 schematically illustrates a second design of the auger screw.Fig. 18 schematically illustrates a third design of the auger screw.Fig. 19 schematically illustrates an alternative design of an agricultural implement.Figs 20-26 schematically illustrates alternative designs of a feed device.DescriptionFig. 1 schematically illustrates an agricultural implement 1, which is towed by a traction vehicle 2 over ground 0 to which at least one type of granular material G is to be distributed by the agricultural implement 1.The traction vehicle 2 may be any type of traction vehicle, including traditional tractors, which tow and / or carry the agricultural implement 1, as well as gantry-type traction vehicles. It is also possible for the agricultural implement to be self-propelled. The traction vehicle, regardless of its type, or the self-propelled agricultural implement, may be driverless, such as autonomous or remote controlled.The agricultural implement 1 may be a seeder, also known as a "drill seeder" or a "seed drill", or a planter, also known as a "precision planter".The agricultural implement 1 comprises an implement frame 110. The agricultural implement 1 may have a connector 111 for towing and / or carrying by the traction vehicle 2. The agricultural implement 1 may, but need not, have one or more ground supports 112, which may take the form of wheels, rollers, or the like.The implement frame 110 may be formed by a single frame section or by two or more frame sections which are movable, such as pivotable, relative to each other, e.g. such that the agricultural implement can be converted between a working state and a transport state.The agricultural implement 1 may comprise a central container 120 for holding an amount of granular material G to be distributed, such as seeds, fertilizer, herbicide and / or pesticide. A feeder 121 may be provided for feeding the granular material G from the central container 120.The agricultural implement 1 may comprise an air drive device 130, such as a fan or a pump, connected to an air supply channel 131, for providing an airflow that can be used for transporting the granular material G from the central container 120 towards a plurality of output units 140.Each output unit 140 is configured to deliver the granular material G to the ground 0. The output units 140 may be arranged side by side, in one or more rows. In some embodiments, adjacent output units 140 may be staggered in a working direction Dw.The implement frame 110 can support further types of ground engaging tools, for e.g. cultivation and / or reconsolidation of the ground 0 before and after seeding / planting, respectively. Such tools can comprise levelling tools, tillage tools (harrow or cultivation tools (such as disc tools or tines)), straw harrows, tines carrying goose foot or wing shares, and / or packer rollers operating in front of and / or behind the output units 140.The granular material G may be injected into the airflow in the air supply channel 131 by the feeder 121.In the embodiment illustrated in fig. 1, the feeder may be a volumetric feeder, or "meter", which would typically comprise one or more feed wheels or screws, the output of which may be connected to the air supply channel 131, optionally via an injection nozzle (not shown).A primary channel 132 may guide the material-laden airflow from the feeder 121 to one or more distributors 133, in which the material-laden airflow may be divided into a plurality of smaller secondary channels 134, which lead to the output units 140. It is possible to provide one secondary channel 134 for each output unit 140, or one secondary channel 134 may supply two or more output units 140 via branch devices.Fig. 2 schematically illustrates an alternative agricultural implement 1, which corresponds to the one disclosed in fig. 1 with the modification that the central feeder 122 is provided in the form of a plurality of uptake zones, into which the granular material G is allowed to fall by gravity from the central container 120, whereby each such uptake zone may be connected to one output unit 140 via the primary channel 132, or where each primary channel 132 may supply two or more output units 140 via branch devices.Such central feeders 122 are disclosed in e.g. WO2016072922A1 and W02020214077A1.Fig. 3 schematically illustrates an output unit 140, comprising an output unit frame 146, which may be connected to the implement frame 110 by a mount device 147. Hence, it is possible that the implement frame 146 may be movably connected to the implement frame 110. The mount device may comprise a parallel linkage, along with a force control device, such as a spring or an actuator (hydraulic, pneumatic, electric).The output unit 140 comprises a feed device 145, which has a material inlet 1451 connected to the secondary channel 134 and optionally an air inlet 1453 for receiving pressurized air from a source 135 of pressurized air.The feed device further has a material outlet 1452 connecting to a delivery tube 141 that is configured to guide the granular material G to its delivery point 1411 in the ground 0.The delivery tube 141 may be rigid and relatively short, typically less than 150 cm, preferably less than about 100 cm, less than about 75 cm or less than about 50 cm.This delivery point 1411 may thus be fixedly arranged, or fixably arranged, relative to the feed device, as opposed to the case where a hose or other flexible structure would be needed to convey the granular material from the feed device to the delivery point 1411.A furrow opening device 142 may be provided in the form of one or more furrow opener discs, and / or a seed knife and / or a seed boot, as the case may be. A seed knife or a seed boot may be connected to the delivery tube 141.Optionally, a press wheel 143 may be provided for pressing the granular material G into the ground 0 once it has been deposited.Optionally, a furrow closing device 144 may be provided for closing the furrow after deposition of the granular material G. The furrow closing device may comprise one or more wheels, levelling tools, or the like.Fig. 4 schematically illustrates a feed device 145 which may have a device housing 1450, a material inlet 1451, a material outlet 1452, an air inlet 1453, a material buffer 1454, a transfer device housing 1455, a transfer screw 1456 and a drive unit 1457.The device housing 1450 may be formed as an integral component, which may define one or more of the material inlet 1451, the material outlet 1452, the air inlet 1453, the buffer 1454 and the transfer device housing 1455.The material inlet 1451 may connect to the material buffer 1454, such that material received from the secondary channel 134 is received in a space forming the material buffer 1454.The material inlet 1451 may be ventilated to allow the airflow transporting the material to be evacuated. The material inlet 1451 may be configured such that when the level of material rises above a predetermined level, the evacuation of the airflow is prevented, such that the flow of material ceases.A transfer device inlet 14551 may be provided in, or in direct connection with, the material buffer 1454, such that material present in the material buffer 1454 is guided into the transfer device 1455, 1456.A bottom 14501 of the device housing, and in particular of a portion of, or provided in, the device housing forming the buffer 1454, may be downwardly inclined towards the transfer device inlet 14551.In some embodiments, the material buffer 1454 of each output unit may be made large enough, such that the central container 120 and associated arrangement 121, 122, 130, 131, 132, 133, 134 for feeding material to the material buffers 1454 are not needed.The material outlet 1452 may be connected downstream of a transfer device outlet 14552, such that material fed by the transfer device 1455, 1456 can be guided to the delivery tube 141.In some embodiments, material arriving at the material outlet 1452 may be allowed to fall through the delivery tube 141 by gravity.In other embodiments, an air inlet 1453 may be provided, such that air is received in an air channel 14531, into which the transfer device outlet 14552 may open, such that material transported by the transfer device 1455, 1456 is effectively injected into an airflow in the air channel 14531, after which the material is carried by the airflow to the material outlet 1452 and through the delivery tube 141.Hence, at an intersection of the transfer device outlet 14552 and the air channel 14531, there may be provided a takeup section, in which the granular material may be picked up, or injected, into the airflow.The end of the helical auger screw 1456 may extend slightly into the air channel 14531, such that the granular material can be more easily picked up by the airflow.The transfer device 1455, 1456 is formed as an auger conveyor, having a helical auger screw 1456 and an auger housing 1455. The helical auger screw 1456 may comprise a screw axle 14561 and a screw blade 14562, the screw blade 14562 having a pitch along the screw axle 14561.The transfer device 1455, 1456 is configured to lift or elevate the granular material G from the transfer device inlet 14551 to the transfer device outlet 14552. Hence, the transfer device inlet 14551 is situated at a lower vertical level than the transfer device outlet 14552.In the illustrated embodiments, the screw axis 14561 (i.e. the axis about which it rotates) extends vertically.Referring to fig. 5, there is illustrated the auger angle a, i.e. the angle of the screw axis 14561 which, when the feed device 140 is in its working position, may be an angle to the vertical direction Dv, which is about 0-45 degs, preferably about 0-40 degs, about 0-30 degs, about 0-20 degs, about 0-10 degs, about 0-5 degs or about 0-1 deg.As is illustrated in fig. 4, the drive unit 1457 may be positioned with its drive axle coinciding with the screw axle 14561 and with an actuator housing positioned below, or at a lower part of, the device housing 1450.As one alternative, a transmission device (not shown) may be provided between the drive unit 1457 and the screw axle 14561, such that the drive axle of the drive unit 1457 may be oriented non-coinciding with he screw axle 14561, such as at an angle thereto.In fig. 6, there is illustrated an alternative embodiment, which is identical to the one illustrated in fig. 4, but where the drive unit 1457 is positioned with an actuator housing positioned above, or at, an upper part of, the device housing 1450.Also in this embodiment, a transmission device may be provided, in order to enable a different orientation and / or positioning of the drive unit 1457.All other aspects of the feed device 145 in fig. 6 may be provided according to any of the feed devices disclosed in any of the other figures.In fig. 7, there is illustrated how a granule sensor 1412 can be provided to the delivery tube 141, whereby a controller 1413 can be caused to control the drive unit 1457 based on a signal from the granule sensor 1412. The granule sensor may be used to indicate a flow of material, and optionally to provide a granule counting function, based on which a granule flow rate may be derived.In particular, any of the feed devices may be connected to a controller 1413 for controlling the operation of at least the drive unit 1457.Any controller 1413 indicated herein may form part of a local controller for the output unit, of a central controller for the entire agricultural implement, of a controller provided in the traction vehicle, or of a cloud based controller. Hence, the controller 1413 may be implemented by means of software run on any suitable hardware platform.All other aspects of the feed device 145 in fig. 7 may be provided according to any of the feed devices disclosed in any of the other figures.In fig. 8, there is illustrated an alternative auger screw 1456', having a blade 14562', with a varying blade pitch. As can be seen in fig. 8, the blade pitch is reduced in the direction from the transfer device inlet 14551 towards the transfer device outlet 14552.Such reduction of blade pitch may be continuous over all or part of a length of the auger screw 1456'.Alternatively, the auger screw 1456' may have a first section, closest to the transfer device inlet 14551 with a first blade pitch and a second section, closest to the transfer device outlet 14552, with the first section presenting a greater blade pitch than the second section. A transition portion may be provided where the first and second sections meet.It is possible, if desirable, to instead provide the auger screw with an increasing blade pitch towards the transfer device outlet 14552, analogously with what was described above.All other aspects of the feed device 145 in fig. 8 may be provided according to any of the feed devices disclosed in any of the other figures.In fig. 9, there is illustrated an alternative feed device 145, in which the incoming airflow is a material-laden airflow, which comprises a first granular material G, which may be e.g. seeds, herbicide, pesticide or fertilizer, such that the material provided at the transfer device outlet 14552 is inserted into the materialladen airflow, such that the resulting airflow at the material outlet 1452 may comprise two, or more types of granular materials.Hence, two or more feed devices 145 may be arranged in series, each adding one type of granular material G to an airflow, such that a combined material-laden airflow is provided at the material outlet 1452.It is also possible to arrange two or more feed devices 145 in parallel, such that they dispense different materials to one or more airflows, which may be merged to a single delivery tube 141.All other aspects of the feed device 145 in fig. 9 may be provided according to any of the feed devices disclosed in any of the other figures.In figs 10a and 10b, there is illustrated how the auger screw 1456 may be immersed to different degrees into the granular material G, resulting in different degrees of loading of the auger screw 1456.In fig. 10a, the auger screw 1456 is immersed into the granular material G present in the device housing, in particular in the material buffer 1454, to a degree corresponding to about 50 % of a turn of the blade 14562.In fig. 10b, the auger screw 1456 is immersed into the granular material G present in the device housing to a degree corresponding to about 150 % of a turn of the blade 14562.The degree to which the auger screw 1456 is immersed into the granular material G may be controlled in various ways.As one example, the level of material present in the device housing may be controlled.As another example, the amount of material allowed to migrate into the auger housing 1455 may be limited, e.g. by an upper limiter.As yet another example, the height of the device housing, in particular of the space forming the material buffer 1454, may be limited, as illustrated in figs 10a, 10b.As a further example, the auger screw 1456 may be axially displaceable to allow adjustment of its extent into the granular material G.In fig. 11, there is illustrated the configuration of the material takeup section according to a first design thereof. This design corresponds to the illustrations provided in figs 4 and 6-9.In the design illustrated in fig. 11, the transfer device outlet 14552 from the auger housing 1455 opens into the air channel 14531, such that the material fed by the auger screw 1456 can be taken up by the airflow in the air channel 14531.The auger screw 1456 may extend substantially perpendicular to a direction of an airflow in the air channel 14531, and thus parallel to a flow cross section of the air channel 14531.In alternative embodiments, the auger screw may extend at an angle smaller than 90 degs to the cross section, such as 25-50 degs, 50-75 degs or 75-90 degs.In fig. 12, there is illustrated a configuration of the material takeup section according to a second design thereof, wherein a constriction 14532 of the air channel 14531 is provided at the transfer device outlet 14552, such that airspeed at the transfer device outlet 14552 is increased for facilitating injection of the granular material into the airflow.In fig. 13, there is a configuration of the material takeup section according to a third design thereof, wherein an airflow is provided along the auger housing 1455 and in a direction which substantially coincides with a feed direction of the auger screw 1456.In particular, the airflow may be provided in a channel 14533 which at least partially, optionally entirely, surrounds the auger housing 1455, such that the airflow may be substantially concentric with the auger housing 1455.The airflow may be directed to flow in substantially the same direction as the material flow in the transfer device 1455, 1456. Hence, the airflow may flow upwardly, as does the granular material flowing in the transfer device 1455, 1456.In fig. 14, there is illustrated a configuration of the material takeup section according to a fourth design thereof, wherein an airflow is provided along the auger housing 1455 and in a direction which is substantially opposite a feed direction of the auger screw 1456.In particular, the airflow may be provided in a channel 14534 which at least partially, optionally entirely, surrounds the auger housing 1455, such that the airflow may be substantially concentric with the auger housing 1455.The airflow may be directed to flow in a substantially opposite direction relative to the material flow in the transfer device 1455, 1456. Hence, the airflow may flow downwardly, opposite the granular material flowing in the transfer device 1455, 1456.In fig. 15, there is illustrated a configuration of the material takeup section according to a fifth design thereof, wherein an airflow is provided along the auger housing 1455 and in a direction which is substantially opposite a feed direction of the auger screw 1456.In the configuration illustrated in fig. 15, there is provided an airflow deflector upstream, as seen relative to the airflow, of the transfer device outlet 14552, said airflow deflector being configured to prevent the airflow from directly impinging on material present at the transfer device outlet 14552.It is understood that each of the various designs of the intersection between the transfer device 1455, 1456 and the air channel 14531, 14533, 14534 may be combined with any of the feed devices disclosed herein.In fig. 16, there is illustrated a first design of the auger screw, in which the auger screw presets a plurality of recesses or through holes 14563, which are sized and adapted for receiving granules of the granular material that is to be transferred by the transfer device 1455, 1456 and which are configured for enhancing the ability of the screw blade to retain granules of the granular material while they are being transported by the transfer device 1455, 1456.The recesses or through holes 14563 may be arranged along a radially outermost edge of the screw blade 14562. It is possible to provide one or further more sets of holes extending along the screw blade 14562.The size and shape of the plurality of recesses or through holes can be selected to fit a particular type of granular material. Hence, it may be advantageous to design the transfer device 1455, 1456 such that the auger screw 1456 can be readily swapped to another auger screw that is adapted for a different type of granular material.In fig. 17, there is illustrates a second design of the auger screw, in which the screw blade 14562 is provided with a plurality of essentially radially extending ridges and / or grooves 14564, which are configured for enhancing the ability of the screw blade to retain granules of the granular material while they are being transported by the transfer device 1455, 1456.Each of the grooves or ridges may be essentially straight. However, it is possible to provide grooves and / or ridges which present a wave pattern, a sawtooth pattern, or the like.The ridges or grooves may be formed to counteract reverse flow of the material along the auger screw, e.g. by having a cross section, in a plane comprising the screw axis 14561, which tapers towards the transfer device inlet 14551.In fig. 18, there is illustrated a third design of the auger screw, in which the screw blade 14562 is generally smooth.However, the screw blade 14562 may be provided with a friction enhancing surface, such as with a surface coating of a rubber material, a silicon material, a PU material or a TPE material. Alternatively, the surface of the screw blade 14562 may be matted or otherwise made rough.It is understood that each of the various designs of the screw blade 14562 may be combined with any of the feed devices disclosed herein.In fig. 19, there is illustrated an alternative design of an agricultural implement, which essentially corresponds to that disclosed with reference to fig. 2, but wherein the central feed device 123 is designed with a plurality of transfer devices 1455, 1456, each of which being configured to output material to a respective primary air channel 131, whereby a respective primary air channel 132 conveys a material laden airflow to respective output units 140, which may be designed as any of the output units disclosed above, or which may be designed as a planter output unit having a disc or drum type singulator, or which may be designed to merely output material directly to ground 0 without further flow tuning or flow equalization.The drive unit 1457 may be provided as one drive unit driving all of the transfer devices 1455, 1456 via a transmission mechanism, as one drive unit for every two, three or four transfer devices 1455, 1456 via respective transmission mechanisms, such that transfer devices 1455, 1456, may be controlled in groups, or as individual drive units for each of the transfer devices 1455, 1456.In fig. 20, there is illustrated a twin feed device, with a single housing 145 with related material inlet 1451 and (optional) air inlet 1453 and with two material outlets 1452a, 1452b, connected to respective delivery tubes 141a, 141b, which may be configured to deliver to different furrows.The device housing 145 may have a common material buffer 1454, from which a pair of transfer devices 1455a, 1456a; 1455b, 1456b may draw granular material to be fed to the respective material outlets 1452a, 1452b.The twin feed device may, as illustrated in fig. 20, be connected to a central container for supply of granular material through the channel 134. However, this is optional, as the twin feed device may also have a sufficiently large material buffer 1454, such that no central container is needed.In fig. 21, there is illustrated a further design of the auger screw 1456 and related auger housing 1455, which can be combined with any of the previously discussed embodiments of the feed device 145. In the design illustrated in fig. 21, the screw blade 14562 presents a varying outer diameter and the auger housing 1455 is conical, such that the displacement increases towards a transfer device outlet 14552.In an alternative version of fig. 21, the displacement may instead increase towards the transfer device inlet 14551.In fig. 22, there is illustrated a further design of the auger screw 1456 and related auger housing 1455, which can be combined with any of the previously discussed embodiments of the feed device 145. In the design illustrated in fig. 22, the auger axle 14561 has a diameter which varies along the axis of rotation Ar, such that the screw blade 14562 presents a varying inner diameter. Hence, the displacement increases towards the transfer device outlet 14552.In an alternative version of fig. 22, the displacement may instead increase towards the transfer device inlet 14551.In fig. 23, there is illustrated a further design of the auger screw 1456 and related auger housing 1455, which can be combined with any of the previously discussed embodiments of the feed device 145. In the design illustrated in fig. 23, the auger screw is, along at least a part of its axial direction, devoid of the auger axle.In embodiments based on fig. 23, the auger screw 1456 may be attached at one or both of its ends to a plate and / or a short axle, which may connect to the drive unit 1457.In fig. 24, there is illustrated a further design of the auger screw 1456 and related auger housing 1455, which can be combined with any of the previously discussed embodiments of the feed device 145. In the design illustrated in fig. 24, the auger screw 1456 is divided into three portions @P1, @P2, @P3, each of which having a respective fixed blade pitch PI, P2, P3, with a transition portion being formed between each pair of portions @P1, @P2; @P2, @P3.Hence, the displacement can be increased in the direction towards the transfer device outlet 14552.In an alternative version of fig. 24, the displacement may instead increase towards the transfer device inlet 14551.In yet further alternative versions of the design of fig. 24, the number of portions @P1, @P2, @P3 can be varied from a minimum of two portions and upwardly.In fig. 25, there is illustrated a further design of the auger screw, which corresponds to the one in fig. 8, and which can be combined with any of the previously discussed embodiments of the feed device 145. In the design illustrated in fig. 25, the blade pitch increases continuously in the direction from the transfer device inlet 14551 towards the transfer device outlet 14552.Hence, the displacement can be increased in the direction towards the transfer device outlet 14552.In an alternative version of fig. 25, the displacement may instead increase towards the transfer device inlet 14551.In fig. 26, there is illustrated a further design of the auger screw 1456 and related auger housing 1455, which can be combined with any of the previously discussed embodiments of the feed device 145. In the design illustrated in fig. 26, the auger axle 14561 presents portions, which are spaced apart along the axis of rotation Ar, and which present different diameters, such that the screw blade 14562 presents different inner diameters. Each of the sections presents a fixed axle auger axle diameter. Hence, the displacement increases stepwise towards the transfer device outlet 14552.In an alternative version of fig. 26, the displacement may instead increase towards the transfer device inlet 14551.

Claims

CLAIMS1. A feed device (145) for feeding granular material from an agricultural implement for distributing said granular material to ground over which the agricultural implement travels, comprising:a device housing (1450),a material inlet (1451), for receiving said granular material in the device housing,a material outlet (1452), for delivering said granular material from the device housing; anda transfer device (1455, 1456) configured for transporting said granular material to the material outlet (1452),characterized in thatthe transfer device (1455, 1456) comprises an auger conveyor (1456), which is configured to elevate said granular material to the material outlet (1452).

2. The feed device as claimed in claim 1, wherein the auger conveyor (1456) presents an axis of rotation (Ar), which, when the feed device (145) is in an operating position, presents an angle (a) to a vertical direction, which is about 0-45 degs, preferably about 0-40 degs, about 0-30 degs, about 0-20 degs, about 0-10 degs, about 0-5 degs or about 0-1 deg.

3. The feed device as claimed in claim 2, wherein the auger conveyor (1456) comprises a helical blade (14562) having a blade pitch, wherein the helical blade presents at least two portions which are spaced apart along an axis of rotation and which present different blade pitches.

4. The feed device as claimed in claim 3, wherein a blade portion which is closer to the material outlet (1452) presents a smaller blade pitch than a blade portion which is further away from the material outlet (1452).

5. The feed device as claimed in claim 3, wherein a blade portion which is closer to the material outlet (1452) presents a greater blade pitch than a blade portion which is further away from the material outlet (1452).

6. The feed device as claimed in any one of the preceding claims, wherein the auger conveyor (1456), along at least a portion of its length, is devoid of auger axle.

7. The feed device as claimed in any one of claims 1-5, wherein the auger conveyor (1456) comprises an auger axle, wherein an auger axle (14561) presents at least two portions which are spaced apart along an axis of rotation (Ar) and which present different axle thicknesses.

8. The feed device as claimed in any one of the preceding claims, wherein a blade outer diameter varies along the axis of rotation (Ar), such that a displacement of the auger conveyor (1456) varies along the axis of rotation (Ar).

9. The feed device as claimed in any one of claims 3-8, wherein at least a portion of the blade (14562) presents enhanced surface friction.

10. The feed device as claimed in any one of claims 3-9, wherein at least a portion of the blade (14562) presents surface variations for engaging granules.

11. The feed device as claimed in claim 10, wherein the screw blade (14562) presents a plurality of recesses or through holes (14563) configured for receiving granules of said granular material.

12. The feed device as claimed in claim 10 or 11, wherein the screw blade (14562) presents a plurality of generally radially extending grooves and / or ridges (14564) configured for receiving granules of said granular material.

13. The feed device as claimed in any one of the preceding claims, wherein the device housing (1450) encloses a material buffer (1454), which is configured to hold an amount of said granular material, whereby the transfer device (1455, 1456) is configured to elevate the granular material from the material buffer (1454) to the material outlet (1452).

14. The feed device as claimed in any one of the preceding claims, further comprising a drive unit (1457), operatively connected to the transfer device (1455, 1456), for driving the transfer device (1455, 1456).

15. The feed device as claimed in claim 14, further comprising a granule sensor (1412), configured to detect granules exiting through the material outlet (1452), and a controller (1413), configured to control the operation of the drive unit (1457) based, at least partially, on a signal from the granule sensor (1412).

16. The feed device as claimed in claim 14 or 15, wherein the drive unit (1457) comprises a drive unit housing, which is arranged below the device housing(1450) .

17. The feed device as claimed in claim 14 or 15, wherein the drive unit (1457) comprises a drive unit housing, which is arranged above the device housing (1450).

18. The feed device as claimed in any one of claims 14-17, wherein the drive unit (1457) is operatively connected to at least two transfer devices (1455, 1456).

19. The feed device as claimed in any one of claims 14-18, wherein said at least two transfer devices (1455, 1455a, 1455b, 1456, 1456a, 1456b) are configured to feed material from a single material inlet (1451).

20. The feed device as claimed in any one of the preceding claims, wherein the material outlet (1452) is concentric with the transfer device (1455, 1456).

21. The feed device as claimed in any one of the preceding claims, wherein the material outlet (1452) is connected to a delivery tube (141).

22. The feed device as claimed in any one of the preceding claims, further comprising an auger screw load limiting arrangement.

23. The feed device as claimed in any one of the preceding claims, wherein the auger screw (1456) is axially displaceable for limiting its immersion into the granular material.

24. The feed device as claimed in any one of the preceding claims, wherein the transfer device (1455, 1456) connects to an air channel (14531), configured for conveying the granular material to the material outlet (1452) by means of an airflow.

25. The feed device as claimed in claim 24, further comprising a material takeup section provided at an uppermost portion of the transfer device (1455, 1456) and an airflow inlet (1453) connecting to the material takeup section, whereby the material takeup section is configured such that material transferred to the material takeup section is picked up by the airflow provided through the airflow inlet (1453) and provided as a material-laden airflow to the material outlet (1452).

26. The feed device as claimed in claim 24 or 25, further comprising a constriction (14532) of said air channel (14531) at a transfer device outlet (14552).

27. The feed device as claimed in any one of claims 24-26, wherein the air channel (14531) extends substantially horizontally at the material outlet (1452).

28. The feed device as claimed in any one of claims 24-26, wherein the air channel (14533) is configured to provide an airflow which is directed along a material flow direction in the transfer device (1455, 1456).

29. The feed device as claimed in any one of claims 24-26, wherein the air channel (14534) is configured to provide an airflow which is directed opposite a material flow direction in the transfer device (1455, 1456).

30. The feed device as claimed in claim 28 or 29, wherein the air channel (14533, 14534) at least partially surrounds an auger housing (1455) of the transfer device (1455, 1456).

31. The feed device as claimed in any one of the preceding claims, further comprising an airflow deflector (14535), positioned upstream of a transfer device outlet (14552), as seen relative to the airflow.

32. An output unit (140) for an agricultural implement, comprising: a furrow opener (142),a delivery tube (141), having a tube inlet and a tube outlet configured to guide material into a furrow opened by the furrow opener, anda feed device (145) as claimed in any one of the preceding claims, wherein the material outlet (1452) of the feed device is connected to the tube inlet.

33. The output unit (140) as claimed in claim 32, further comprising an output unit frame (146) supporting said furrow opener (142), the delivery tube (141) and optionally the feed device (140).

34. An agricultural implement (1) for distributing granular material to ground over which the agricultural implement travels, comprising a plurality of output units (140) as claimed in claim 32 or 33.

35. The agricultural implement (1) as claimed in claim 34, further comprising a central material container (120) and a feed arrangement (121, 122, 123, 130, 131, 132, 133, 134) for feeding material from the central container (120) to at least some of the output units (140).

36. The agricultural implement as claimed in claim 35, wherein the feed arrangement (121, 122, 123, 130, 131, 132, 133, 134) comprises one or more primary material feed lines (132) for pneumatically guiding material from the central container.

37. The agricultural implement as claimed in claim 36, wherein each of the primary material feed lines (132) are connected directly to a respective one of the output units (145).

38. The agricultural implement as claimed in claim 36, wherein the feed arrangement (121, 122, 123, 130, 131, 132, 133, 134) comprises at least one distributor (133) having a distributor inlet which is connected to a primary material feed line (132) and at least two distributor outlets, which are connected via secondary material feed lines (134) to a respective one of the output units (140).

39. A method of controlling flow of a first granular material in an agricultural implement (1), comprising:feeding a respective flow of said first granular material to a plurality of output units (140) of the agricultural implement (1),at each of said output units:receiving the flow of said first granular material in a feed device (140), transferring said first granular material upwardly to a material outlet (1452) using an auger conveyer (1456), andguiding said first granular material from the material outlet (1452) towards ground (0) to which the material is to be deposited.

40. The method as claimed in claim 39, wherein said guiding is performed at least partially by means of an airflow.

41. The method as claimed in claim 40, further comprising constricting said airflow in order to increase a velocity thereof at a position where said granular material transported by said auger conveyer (1456) merges with said airflow.

42. The method as claimed in any one of claims 39-41, further comprising providing a second granular material and guiding said second granular material together with said first granular material.

43. The method as claimed in any one of claims 39-42, wherein the auger conveyor (1456) comprises an auger screw (1456) and wherein the method comprises limiting a loading of an auger screw by immersing it into the granular material present in the device housing by less than about 250 % of a turn of a screw blade, preferably about 200-250 %, about 150-200 %, about 100-150 %, about 75-100 %, about 50-75 %, about 25-50 % or about 5-25 %.