FIELD HACKERS

Description

[0001] The invention relates to a field chopper with several working elements for carrying out and / or supporting agricultural work according to the preamble of claim 1.

[0002] The forage harvester in question has several working elements for performing and / or supporting agricultural work. One of the working elements is a chopping element for chopping a crop stream taken up by the forage harvester. This chopping element usually has a chopping drum with chopping knives arranged thereon, as well as a counter-cutter arrangement with a counter-blade that interacts with the chopping knife arrangement.

[0003] During the forage harvester's work cycle, the chopping knives attached to the chopping drum wear down over time as the crop is chopped. In particular, wear-related material wears away at the cutting edges of the chopping knives, resulting in a reduction in cutting quality and, due to the increased power requirements of the chopping drum, a lower throughput.

[0004] The cutting sharpness of the chopper blades has a significant impact on the operating costs of a forage harvester. If they are sharpened infrequently, the efficiency of the forage harvester decreases, resulting in higher costs due to the increased energy consumption. However, sharpening the chopper blades too frequently leads to increased blade wear and requires them to be replaced more frequently, which also increases operating costs. Assessing whether the cutting edges of the chopper blades are sharp enough or whether they need to be sharpened is sometimes difficult for the forage harvester operator to assess from the cab during agricultural work. Stopping agricultural work and manually checking the cutting sharpness is time-consuming and requires considerable experience from the operator.

[0005] To determine the optimal time for regrinding chopper blades, EP 2 225 931 B1 proposes deriving a forecast of the expected wear of the chopper blades based on at least one crop and / or machine parameter determined during the harvesting process. This is already producing good results. However, there is a need to determine the cutting sharpness of the chopper blades even more reliably and precisely. Another forage harvester is disclosed in EP 2 436 258 A1.

[0006] The invention is based on the problem of designing and developing the known field chopper in such a way that the cutting sharpness can be determined as reliably and precisely as possible in order to determine a suitable time for grinding the chopper knives.

[0007] The above problem is solved in a forage harvester according to the preamble of claim 1 by the features of the characterizing part of claim 1.

[0008] The fundamental consideration is that the slippage of the chopping element increases along with the increasing wear of the chopping blades. In this respect, slippage is a suitable parameter for deriving a measure of the cutting sharpness of the chopping blades. Slippage is particularly suitable because it is particularly easy to measure and, with increasing wear of the chopping blades, under otherwise constant boundary conditions, the torque required to chop the crop flow and, consequently, the slippage of the chopping element also increases. A corresponding determination of the cutting sharpness measure can be optimally performed by a driver assistance system of the forage harvester.

[0009] In particular, it is proposed that the driver assistance system is configured in such a way that a slip is determined in the drive train of the chopper and that this slip is processed in the analysis and evaluation unit in such a way that a measure of the cutting sharpness of the chopper blades is derived.

[0010] A preferred embodiment of the chopping device is described in claim 2. It has proven effective for efficient chopping of the crop stream. According to claim 3, a grinding device can be provided.

[0011] Claims 4 and 5 describe preferred embodiments of the drive train, which allow a reliable drive of the chopper and a reliable and precise determination of the slip.

[0012] Claims 6 and 7 describe a sensor arrangement by means of which the slip can be determined and further boundary conditions for deriving a reliable and precise measure of the cutting sharpness of the chopping knives can be determined.

[0013] Claims 8 to 11 describe preferred embodiments of the analysis and evaluation unit and the processing of the slippage therein to derive the measure of cutting sharpness. This is preferably done by incorporating at least one characteristic map in the manner described in these claims.

[0014] Claims 12 to 14 describe preferred forms of visualizing the measure of cutting sharpness. According to the embodiment of claim 12, the cutting sharpness is displayed in a display unit, so that an operator is always informed about the cutting sharpness of the chopping knives during the harvesting process. The operator does not have to leave the driver's cab for this purpose. The assessment of the current cutting sharpness can be further facilitated using a scale as proposed in claim 13. The icons of this scale can be set and / or moved by the operator, as described in claim 14, to further facilitate the assessment of the currently displayed cutting sharpness during the work process.

[0015] According to a further teaching according to claim 15, which has independent significance, a method for operating a forage harvester as such is claimed. Reference is made to all statements regarding the proposed forage harvester.

[0016] In the following, the invention is explained in more detail with reference to a drawing which merely represents exemplary embodiments. In the drawing, Fig. 1 shows a proposed forage harvester and an enlarged view of the chopping element of the forage harvester, Fig. 2 shows two exemplary characteristic diagrams for deriving a measure of the cutting sharpness of the chopping knives, Fig. 3 shows a display unit for displaying the cutting sharpness for the operator of the forage harvester.

[0017] In the Fig. 1 A proposed forage harvester 1 is shown. It is designed here as a self-propelled forage harvester 1. The forage harvester 1 has several working elements 2 for performing and / or supporting agricultural work, as well as a drive arrangement 3 for driving the working elements 2 and a driver assistance system 4 for controlling and / or monitoring the working elements 2.

[0018] One of the working elements 2 is a chopping element 5 for chopping a crop stream 6 taken up by the forage harvester 1. The chopping element 5 is, as shown in the Fig. 1 shown, driven by the drive assembly 3 via a drive train 7. It has a chopper blade assembly 8 with chopper blades 9. During the performance of agricultural work, in this case a harvesting process, the chopper blades 9 wear out. They must therefore be sharpened from time to time to ensure efficient operation of the forage harvester 1.

[0019] Furthermore, the driver assistance system 4 has, according to the proposal, an analysis evaluation unit 10.

[0020] It is essential that the driver assistance system 4 is configured in such a way that slippage is determined in the drive train 7 of the chopping element 5, and this slippage is processed in the analysis and evaluation unit 10 in such a way that a measure of the cutting sharpness of the chopping blades 9 is derived. The slippage of the chopping element 5 has proven to be a particularly reliable and precise indicator for determining cutting sharpness.

[0021] Determining the slip allows for a simple, continuous, or cyclical determination of the cutting sharpness of the chopping blades 9 during agricultural work of the forage harvester 1. This ensures that the operator of the forage harvester 1 is constantly informed about the cutting sharpness, especially the current cutting sharpness, even during agricultural work. They can easily and effectively schedule the resharpening of the chopping blades 9 into the subsequent agricultural work process.

[0022] During agricultural work by the forage harvester 1, in the exemplary embodiment during the harvesting process, the crop is collected as a crop stream 6 by an attachment 11 and fed to an intake device 12. The intake device 12 in the exemplary embodiment has a first pair of intake rollers 13 and a second pair of intake rollers 14. They serve to draw in and pre-press the collected crop stream 6. The intake rollers 13, 14 can adjust the pre-pressing force on the crop stream 6, as well as the intake speed of the crop stream 6 via their drive speed, in order to adapt the forage harvester 1 to changing crop quantities. The intake device 12 is another working element of the forage harvester 1.

[0023] The chopping element 5 is arranged downstream of the intake device 12. As already described, the chopping element 5 has a chopping blade assembly 8. The chopping blade assembly 8 has a chopping drum 15 on which the chopping blades 9 of the chopping blade assembly 8 are arranged. Furthermore, the chopping element 5 has a counter-cutter assembly 16 with a counter-blade 17 that interacts with the chopping blade assembly 8. The rotating chopping drum 15 chops the crop supplied in the form of the crop stream 6 by chopping it.

[0024] Furthermore, the forage harvester 1 can have a grinding device 18, which is driven by a drive and shown only schematically, with a grinding tool for grinding the chopping blades 9. This allows the chopping blades 9 to be sharpened at cyclical intervals without having to be removed.

[0025] The crop stream 6 of shredded crop material emerging from the chopping device 5 can be fed to a preferably provided post-processing device 19. This is also a working device 2 of the forage harvester 1. The post-processing device 19, also referred to as a conditioning device or corn cracker, serves to break down the crop material, in particular corn kernels in the crop stream 6, in order to increase its usability and energy yield when used as animal feed or in a biogas plant. Such post-processing devices 19 generally have a profiled pair of rollers, with the rollers 20 usually being driven at different speeds.

[0026] From the chopping element 5, or the preferably provided post-processing device 19, the crop flow 6 reaches a post-acceleration device 21. The post-acceleration device 21 is a working element 2. The post-acceleration device 21 conveys the crop flow 6 through a conveyor shaft 22 and an adjoining ejection device 23 designed as a discharge chute to a transport vehicle - not shown - traveling near the forage harvester 1.

[0027] The drive assembly 3 is here and preferably designed as an internal combustion engine. The drive assembly 3 drives the working elements 2 via at least one drive train 7. Here and preferably, the drive train 7 has a belt drive 24, via which the chopping drum 15 is driven. The belt drive 24 is here designed as a V-belt drive. As shown in the Fig. 1As shown, the post-acceleration device 19 is also driven via the belt drive 24. Additionally, a secondary drive train, particularly a hydraulic one, can be provided, via which other working elements 2 of the forage harvester 1 are driven.

[0028] The determined slippage—which is processed in the analysis and evaluation unit to derive the measure of the cutting sharpness of the chopping blades 9—is preferably determined as described below. This refers to the slippage, in particular the expansion slippage, of the belt drive 24 on the chopping drum 15. The slippage here is the slippage between a belt pulley 27, which is connected to the chopping drum 15, in particular in a rotationally fixed manner, and the driving belt 26.

[0029] In the exemplary embodiment, and preferably, a roller 25 is arranged in the drive train 7 for determining a reference speed, wherein the slip is determined using the reference speed. In the exemplary embodiment, the roller 25 is arranged downstream of the chopping element 5 in the drive train 7. This means that in the direction of rotation of the belt 26 of the belt drive 24, the roller 25 is arranged on the output side of the chopping element 5. Here, the roller 25 is arranged directly downstream of a belt pulley 27 in the belt drive 24 that is connected in a rotationally fixed manner to the chopping drum 15. This means that no further power consumers are arranged along the belt 26 between the belt pulley 27 and the roller 25. In this way, a slip that can be clearly assigned to the load on the chopping drum 15 can be determined, especially when other working elements 2 are driven via the belt 26.

[0030] To determine the slip in the drive train 7 of the chopping device 5, the driver assistance system 4 has a sensor arrangement 28. The sensor arrangement 28 has a speed sensor 29 for determining the speed of the chopping drum 15 and a speed sensor 30 for determining the reference speed of the roller 25. The slip of the chopping drum 15 is determined from the speed of the chopping drum 15 and the reference speed of the roller 25. The analysis and evaluation unit 10 can then process this slip and derive a measure of the cutting sharpness of the chopping blades 9.

[0031] Additionally or alternatively, the sensor arrangement 28 may comprise a layer height sensor 31 for determining the layer height of the crop flow 6 in the forage harvester 1. As shown in the Fig. 1 As shown, the layer height sensor 31 is arranged in the intake device 12 of the forage harvester 1.

[0032] Furthermore, a moisture sensor 32 can be provided for determining the moisture content of the crop stream 6. This is preferably arranged in the intake device 12 of the forage harvester 1 and / or in a discharge spout of the forage harvester 1. The moisture sensor 32 is preferably designed as an NIR (near-infrared) sensor.

[0033] Additionally, a sensor 33 can be provided for detecting the flow velocity of the crop stream 6 in the forage harvester 1. In the exemplary embodiment, the flow velocity of the crop stream 6 is preferably the intake velocity of the crop stream 6. Here, the sensor 33 is preferably also arranged in the intake device 12 of the forage harvester 1.

[0034] The sensor 33 for detecting the flow velocity can be one or more speed sensors which detect the speed of one or more feed rollers 13, 14.

[0035] The analysis and evaluation unit 10 processes the acquired sensor data 28, in particular the sensor-determined slip and / or the layer height and / or the humidity and / or the flow velocity, and derives the measure of the cutting sharpness based on these.

[0036] Here, the analysis and evaluation unit 10 creates a characteristic map 34 based on the acquired sensor data of the sensor arrangement 28 and / or adapts and / or selects a characteristic map 34, for example, a stored one. The characteristic map 34 can, for example, be in the form of a polynomial function.

[0037] The characteristic map 34 is determined or adjusted based on the sensor-determined slip and / or the parameters "layer height" and / or "humidity" and / or "flow velocity." The values for these parameters are provided here, and preferably for determining the characteristic map 34, by the sensor arrangement 28 with the previously described sensors 29, 30, 31, 32, 33.

[0038] The analysis and evaluation unit 10 then derives a measure of cutting sharpness from the recorded sensor data or, in particular, the current characteristic map 34. The use of a characteristic map 34 has proven particularly advantageous for reliably and precisely deriving the measure of cutting sharpness. Using the characteristic map 34, the portion of the load on the chopping element that is due to the blunting of the chopping blades 9 can be determined to derive the measure of cutting sharpness.

[0039] The analysis and evaluation unit 10 preferably starts at the beginning of the agricultural work process and / or upon entry into a field with an initial characteristic map as characteristic map 34, which is adapted to the agricultural work process during the agricultural work process. Here, and preferably, the adaptation takes place based on the sensor data of the sensor arrangement 28. The characteristic map 34 is preferably adapted to the agricultural work process during the agricultural work process, in particular cyclically or continuously.

[0040] Two different characteristic maps 34 for deriving the cutting sharpness are shown as examples in the Fig. 2shown. The characteristic map 34 with dashed lines is a characteristic map 34 for chopping blades 9 with a high cutting sharpness, while the characteristic map 34 with solid lines is a characteristic map 34 for cutting blades 9 with a low cutting sharpness. It was available in the analysis-evaluation unit at a later time. Fig. 2 shows the two characteristic maps 34 qualitatively for a constant flow velocity, where Sh is the layer height, F is the moisture content of the crop, and S HT is the determined slip. The characteristic map 34 here is a characteristic map 34 with the variables slip and / or layer height and / or moisture and / or flow velocity, in particular the intake velocity.

[0041] Here, and preferably, the analysis and evaluation unit 10 derives the measure of cutting sharpness from at least one characteristic of the characteristic map 34, for example a gradient, and / or a change in the characteristic map 34 and / or from comparison data stored in the analysis and evaluation unit 10. The comparison data were preferably generated from expert knowledge and / or through simulation and / or through field tests. The cutting sharpness can be easily derived from the at least one characteristic and / or the change in the characteristic map 34 and / or the comparison of the characteristic map 34 with the stored comparison data. The comparison data can, in particular, be a comparison characteristic map or comparison characteristics for the characteristic map 34.

[0042] When deriving the measure of cutting sharpness, here from the characteristic map 34, the parameters for the layer height of the crop stream 6 and / or the moisture content of the crop stream 6 and / or the flow velocity of the crop stream 6, in particular the speed of the intake rollers, are assumed to be a fixed observation point P. Alternatively, several observation points can also be used to derive the measure of cutting sharpness. For these, the parameters for the layer height of the crop stream 6 and / or the moisture content of the crop stream 6 and / or the flow velocity of the crop stream 6, in particular the speed of the intake rollers, are preferably also assumed to be fixed. Furthermore, when deriving the measure of cutting sharpness, an average value from several observation points P can be assumed.

[0043] The analysis and evaluation unit 10 has a computing unit for processing the sensor data of the sensor arrangement 28, in particular for adapting the characteristic map 34, and for deriving the measure of the cutting sharpness.

[0044] By deriving the measure of cutting sharpness, the cutting sharpness can be easily visualized for operator B. This provides the operator with an overview of the current cutting sharpness of the chopping blades 9 during agricultural work.

[0045] In the exemplary embodiment, the driver assistance system 4 has a display unit 35 for this purpose. The display of the display unit 35 is in the Fig. 3 The driver assistance system 4 displays the cutting sharpness in the form of a bar chart 36. The bar chart 36 is curved in the exemplary embodiment. The display unit 35 is as shown in the Fig. 1 shown arranged in a driver's cab 37 of the forage harvester 1.

[0046] Fig. 3shows that the cutting sharpness is displayed on the display unit 35 using a scale 38. In the exemplary embodiment, this is a percentage scale ranging from 0 to 100 percent. 0% means very low cutting sharpness, i.e. blunt chopping knives 9, and 100% means very high cutting sharpness, i.e. very sharp chopping knives 9. Furthermore, the scale 38 has a minimum sharpness icon 39 and / or an initial sharpness icon 40. The minimum sharpness icon 39 indicates a cutting sharpness to which the chopping knives 9 should be resharpened. The initial sharpness icon 40 indicates a cutting sharpness that was achieved with the last resharpening. For orientation, the operator B of the forage harvester 1 can set and / or move the position of the minimum sharpness icon 39 and / or the initial sharpness icon 40 on the scale 38. This gives him a simple overview of the current cutting sharpness.

[0047] Based on this display, the operator can easily select a suitable time to resharpen the chopping blades 9 and start a grinding process. The operator can preferably select or specify the number of grinding cycles.

[0048] After a grinding process with the number of grinding cycles selected by the operator, the new position of the initial sharpness icon 40 indicates to operator B the degree of cutting sharpness the chopping knives 9 have regained as a result of the grinding process. This occurs here, and preferably only after the harvesting process has been resumed or a new harvesting process has begun. Based on this, operator B can adjust the number of grinding cycles to be performed for the next grinding process.

[0049] Preferably, the driver assistance system 4 is designed such that, in particular when starting the forage harvester 1 and / or when selecting the corresponding display of the cutting sharpness, it suggests a preferred position of the minimum sharpness icon 39 and / or initial sharpness icon 40 or sets this or these automatically.

[0050] In particular, the driver assistance system 4 can automatically set the minimum sharpness icon 39 depending on the crop that is currently being harvested or is to be harvested. List of reference symbols

[0051] 1Forage harvester 2Working elements 3Drive arrangement 4Driver assistance system 5Chopping element 6Crop flow 7Drive train 8Chopping knife arrangement 9Chopping knife 10Analysis and evaluation unit 11Front attachment 12Intake device 13Intake rollers 14Intake rollers 15Chopping drum 16Counter-cutter arrangement 17Counter-cutter 18Grinding device 19Follow-up device 20Rollers 21Post-acceleration device 22Conveyor chute 23Ejection device 24Belt drive 25Roller 26Belt 27Belt pulley 28Sensor arrangement 29Speed sensor 30Speed sensor 31Layer height sensor 32Moisture sensor 33Sensor for detecting the flow velocity 34Characteristic map 35Display unit 36Bar chart 37Driver's cab 38Scale 39Minimum sharpness icon 40Output sharpness icon BOperator PObservation point

Claims

1. A forage harvester with a plurality of working units (2) for carrying out and / or supporting agricultural work, with a drive assembly (3) for driving the working units (2) and with a driver assistance system (4) for controlling and / or monitoring the working units (2), wherein one working unit (2) is a chopping unit (5) for chopping a flow of harvested material (6) picked up by the forage harvester (1), wherein the chopping unit (5) is driven from the drive assembly (3) via a drive train (7), wherein the chopping unit (5) has a chopping knife assembly (8) with chopping knives (9) and wherein the driver assistance system (4) has an analysis / evaluation unit (10), characterized in that the driver assistance system (4) is configured in a manner such that a slippage in the drive train (7) of the chopping unit (5) is determined and this slippage is processed in the analysis / evaluation unit (10) in a manner such that a measure of the cutting sharpness of the chopping knives (9) is derived, wherein the driver assistance system (4) has a sensor assembly (28) for the determination of the slippage in the drive train (7) of the chopping unit (5).

2. The forage harvester according to claim 1, characterized in that the chopping knife assembly (8) has a chopping drum (15) on which the chopping knives (9) are disposed, and in that the chopping unit (5) has a shear bar assembly (16) with a shear bar (17) which cooperates with the chopping knife assembly (8).

3. The forage harvester according to claim 1 or claim 2, characterized in that the forage harvester (1) has a sharpening device (18) which can be driven by a drive, with a sharpening tool for sharpening the chopping knives (9).

4. The forage harvester according to one of the preceding claims, characterized in that the drive train (7) has a belt drive (24), via which the chopping drum (15) is driven, and in that the slippage which is determined is the slippage of the belt drive (24) on the chopping drum (15).

5. The forage harvester according to claim 4, characterized in that an idler pulley (25) for the determination of a reference speed is disposed in the drive train (7), in particular downstream of the chopping unit (5), wherein the slippage is determined with the reference speed, preferably in that the idler pulley (25) is disposed in the belt drive (24) directly downstream of a belt pulley (27) of the chopping drum (15) which is connected to the chopping drum (15) in a manner which is fixed against rotation.

6. The forage harvester according to claim 5, characterized in that the sensor assembly (28) has a speed sensor (29) for the determination of the speed of the chopping drum (15) and a speed sensor (30) for the determination of the reference speed of the idler pulley (25) and in that the slippage of the chopping drum (15) is determined from the speed of the chopping drum (15) and from the reference speed.

7. The forage harvester according to claim 6, characterized in that the sensor assembly (28) has at least one sensor (31, 32, 33) from the group comprising: a layer height sensor (31) for determining the layer height of the flow of harvested material (6) in the forage harvester (1), wherein in particular, the layer height sensor (31) is disposed in the intake device (12) of the forage harvester (1), a moisture sensor (32) for determining the moisture content of the flow of harvested material (6) in the forage harvester (1), wherein in particular, the moisture sensor (32) is disposed in the intake device (12) and / or in the ejection manifold of the forage harvester (1), a sensor (33) for the detection of the flow rate of the flow of harvested material (6) in the forage harvester (1), wherein preferably, the sensor (33) is disposed in the intake device (12).

8. The forage harvester according to claim 7, characterized in that, on the basis of the detected sensor data of the sensor assembly (28), in particular from the sensorially determined slippage and / or from the "layer height" and / or "moisture content" and / or "flow rate" parameters, the analysis / evaluation unit (10) generates a characteristic diagram (34) and / or adjusts a characteristic diagram (34) and / or selects a characteristic diagram (34).

9. The forage harvester according to one of claims 6 to 8, characterized in that with the commencement of the agricultural operating procedure and / or entry into a field, the analysis / evaluation unit (10) starts up with an initial characteristic diagram as the characteristic diagram (34) which is adapted to the agricultural operating procedure during the course thereof, in particular on the basis of sensor data from the sensor assembly.

10. The forage harvester according to claim 9, characterized in that the analysis / evaluation unit (10) derives the measure of the knife sharpness from the characteristic diagram (34), preferably in that the analysis / evaluation unit (10) derives the measure of the cutting sharpness from at least one characteristic feature of the characteristic diagram (34) and / or from a variation in the characteristic diagram (34) and / or by comparison with comparative data.

11. The forage harvester according to claim 9 or claim 10, characterized in that during the derivation of the measure of the cutting sharpness, in particular from the characteristic diagram, the parameters for the layer height of the flow of harvested material (6) and / or the moisture content of the flow of harvested material (6) and / or the flow rate of the flow of harvested material (6), in particular the speed of an intake roller (13, 14), are assumed to be at least one fixed observation point (P).

12. The forage harvester according to one of the preceding claims, characterized in that the driver assistance system (4) has a display unit (35) for displaying the cutting sharpness, preferably in the form of a bar graphic (36).

13. The forage harvester according to one of the preceding claims, characterized in that the cutting sharpness is displayed on the display unit (35) with the aid of a scale (38), wherein the scale (38) has a minimum sharpness icon (39) which displays a cutting sharpness to which the chopping knives (9) are re-sharpened, and / or an initial sharpness icon (40) which displays a cutting sharpness which was obtained with the last re-sharpening.

14. The forage harvester according to claim 13, characterized in that the position of the minimum sharpness icon (39) and / or of the initial sharpness icon (40) on the scale (38) can be set and / or displaced by the operator.

15. A method for operating a forage harvester (1) according to one of claims 1 to 14, characterized in that a slippage in the drive train (7) of the chopping unit (5) is determined and this slippage is processed in the analysis / evaluation unit (10) in a manner such that a measure of the cutting sharpness of the chopping knives (9) is derived.