METHOD FOR OPERATING A HEADER ATTACHED TO A RECORDING DEVICE OF A SELF-PROPELLED COMBINE HARVESTER AND SELF-PROPELLED COMBINE HARVESTER WITH A SEGMENTED HEADER

Description

[0001] The present invention relates to a method for operating an attachment arranged on a receiving device of a self-propelled combine harvester according to the preamble of claim 1. Furthermore, the present invention relates to a self-propelled combine harvester for carrying out such a method according to claim 12.

[0002] A front attachment comprising a central section and two side sections, each of which is pivotally connected to the central section by a frame joint about a pivot axis oriented in the direction of travel of the combine harvester, wherein the respective side section can be pivoted relative to the central section about the pivot axis transversely to the direction of travel by means of an actuator controlled by a control device, is guided with regard to its height, i.e. its distance from the ground, and in the transverse direction, i.e. its position transversely to the direction of travel. The side sections are supported by position-controlled support wheels arranged on the outside of the side sections in their rear area, while the side sections can move freely about the pivot axis relative to the central section. The height of the central section is adjusted by means of hydraulic cylinders arranged on the support device.For transverse guidance of the attachment, the center segment is pivoted about a pendulum axis relative to the mounting device.

[0003] A method for operating an attachment arranged on a receiving device of a self-propelled combine harvester is known from WO 2020 / 185873 A1.

[0004] A method according to the preamble of claim 1 is also known from US 2021 / 185917 A1.

[0005] Based on the above-mentioned prior art, the invention is based on the object of developing a method for operating a front attachment of the type mentioned above, which is arranged on a receiving device of a self-propelled combine harvester, as well as a self-propelled combine harvester, which is characterized by improved tracking of the side sections of the front attachment when adapting to a changed ground contour.

[0006] This problem is solved from a process engineering perspective based on the preamble of claim 1 in conjunction with its characterizing features. Furthermore, this problem is solved from a device engineering perspective based on the preamble of claim 12 in conjunction with its characterizing features. The dependent claims that follow therefrom represent advantageous developments of the invention.

[0007] According to claim 1, a method is proposed for operating a front attachment arranged on a receiving device of a self-propelled combine harvester, wherein the front attachment comprises a central section and two side sections, each of which is pivotably connected to the central section by a frame joint about a pivot axis oriented in the direction of travel. The respective side section is pivotable relative to the central section about the pivot axis transversely to the direction of travel by means of an actuator controlled by a control device. A vertical distance of the front attachment from the ground is adaptively adjusted by at least one hydraulic cylinder on the receiving device. According to the invention, for ground guidance of the front attachment, the positioning of the side sections relative to the central section is controlled or regulated independently of a height and transverse guidance of the front attachment controlled by the combine harvester.The fundamental idea is that the position of the side sections is controlled independently or decoupled from the combine harvester's height and lateral guidance. No active lateral guidance of the front attachment by the combine harvester is required. The height guidance of the front attachment by the combine harvester has no influence on the positioning of the side sections. Each side section can react to changes in the ground contour, with the positioning of the side sections occurring independently of the height and lateral guidance of the front attachment as a whole. This allows for optimized adaptation to the existing ground contour.

[0008] According to the invention, the side sections are controlled or regulated taking into account a selectable operating mode for ground guidance of the front attachment, whereby the operating modes are selected from the group "cutting height control", "ground pressure control" and "cutting height preselection".

[0009] One of the operating modes can be selected using an operator terminal or another input / output unit connected to the control device. For example, in the "cutting height control" operating mode for ground guidance, the distance of the attachment relative to the ground is specified by entering at least one setpoint. In the "ground pressure control" operating mode for ground guidance, ground guidance is based on a preset ground pressure by placing the attachment on the ground with a weight percentage of the total weight of the attachment specified as a setpoint. The ground pressure exerted on the ground is adjusted by controlling at least one hydraulic cylinder on the pick-up device via the control device. In the "cutting height preselection" operating mode for ground guidance, the angle of inclination of the pick-up device relative to the longitudinal axis of the combine harvester is set to a preset setpoint.

[0010] Preferably, the positioning of the side sections can be performed independently of one another by the respective actuator. The actuator can be designed as a linear drive, in particular as a hydraulic cylinder. The hydraulic cylinder is preferably designed as a double-acting hydraulic cylinder. The respective actuator connects frame elements of the side sections and the central section to one another, so that the respective side section can be pivoted vertically about the frame joint relative to the central section.

[0011] In particular, the control device can receive and evaluate measurement signals from at least two sensors arranged at a distance from each other on the respective side section and the central section, from which a respective distance of the side sections and the central section from the ground is determined. In particular, one sensor of each side section and one sensor of the central section is arranged adjacent to the pivot axis. At least one further sensor is arranged distal to the central section in the region of the outer ends of the side sections.

[0012] The positioning of the respective side section can be carried out independently by the respective actuator depending on a sensor-determined distance difference of the respective side section to the ground.

[0013] Preferably, in the "cutting height control" operating mode, the position of the respective side section relative to the center section can be controlled depending on a distance difference between a distance to the ground detected at the outer end of the side section and a distance to the ground detected in the region of the pivot axis by controlling the actuator until this distance difference is zero. The actuator is controlled by the control device to pivot the respective side section until the distance difference between the distance to the ground detected at the outer end of the side section and the distance to the ground detected in the region of the pivot axis is zero.

[0014] Further preferably, in the "ground pressure control" operating mode, the attachment can be placed on the ground with a preset weight percentage of the total weight as a target value, which is set by applying pressure to the at least one hydraulic cylinder. It is provided that, to control the positioning of the respective side section, the actuator can be controlled depending on the target value and the partial weight of the respective side section, so that the side section is placed on the ground with its corresponding partial weight percentage. The preset weight percentage with which the attachment is placed on the ground results from the pressure in the at least one hydraulic cylinder. With actuators designed as hydraulic cylinders, the positioning of the side sections can be achieved based on the pressure in the respective hydraulic cylinder between the central section and the respective side section.The control device can regulate the pressure in the respective hydraulic cylinder based on the partial weight with which the respective side section is to be placed on the ground.

[0015] Further preferably, in the "cutting height preselection" operating mode, an angle between the pickup device and the combine harvester can be preset to specify a cutting height target value. It is provided that, for positioning the respective side section, it is detected whether at least one of the sensors of the respective side section has or detects contact with the ground when the cutting height target value is set. This allows different operating situations in which the front attachment can be operated to be recorded. For example, in an operating situation in the "cutting height preselection" operating mode, the front attachment can be raised by the pickup device so far that none of the sensors contact the ground. This could be the case, for example, during a high cut.In an alternative operating situation in the "cutting height preselection" operating mode, the cutting height setpoint is selected such that the attachment is so close to the ground that at least one sensor has or detects ground contact.

[0016] If it is detected that all sensors are without contact with the ground, the respective side section can be moved into a central position by controlling the respective actuator, in which the respective side section is positioned essentially in alignment with the central section.

[0017] However, if at least one of the sensors is detected to be in contact with the ground, the positioning of the respective side section can be carried out according to the "cutting height control" operating mode. This can prevent a collision of the respective side section with the ground in the "cutting height pre-selection" operating mode.

[0018] In particular, when operating without selecting an operating mode, the positioning of the respective side sections can be carried out according to the "cutting height preselection" operating mode. When operating without selecting an operating mode, the current travel speed of the combine harvester or the manual raising or lowering of the front attachment are monitored. If the travel speed of the combine harvester exceeds a threshold, for example, 2 km / h, or if the front attachment is manually raised or lowered, the positioning of the side sections is controlled analogously to the "cutting height preselection" operating mode to ensure that the side sections are only moved relative to the center section when no people are in the area of ​​the side sections.

[0019] Preferably, in order to determine the position of a respective side section relative to the central section, a difference between a distance to the ground detected at the outer end of the side section by at least one sensor and a distance to the ground detected in the region of the pivot axis by at least one sensor can be determined.

[0020] For this purpose, measurement signals from a sensor arranged on the central section and on the side section adjacent to the pivot axis can be evaluated in the area of ​​the pivot axis to determine the distance to the ground.

[0021] According to a teaching according to claim 13, which has independent significance, a self-propelled combine harvester with an attachment, in particular an attachment designed as a band cutter or draper, for carrying out the proposed method is claimed as such. Reference may be made to all explanations of the proposed method that are suitable for explaining the working machine.

[0022] In particular, sensors designed as sensing arms can be arranged on the underside of the attachment to detect the distance to the ground. The sensing arms are preferably arranged at the smallest possible distance from the cutter bar in order to be able to detect changes in the ground contour in a timely manner. In this case, one sensing arm each of the respective side section and the central section can be arranged adjacent to the pivot axis. In particular, at least one further sensing arm can be arranged distal to the central section in the region of the outer ends of the side sections. Particularly preferably, two sensing arms are arranged at a distance from one another at the outer ends of the side sections, the distance between said sensing arms being smaller than the distance to the sensing arm of the side section arranged adjacent to the pivot axis.

[0023] Alternatively, support arms pivotable about a transverse axis can be arranged on the central section and the side sections, which support a knife bar, wherein two sensors are provided in each case to detect a vertical deflection of the support arms of the central section and the side sections, wherein the two sensors of the central section are each designed as a measuring shaft connected in a rotationally fixed manner to at least one of the support arms of the central section, and the two sensors of the respective side section are each designed as a measuring shaft connected in a rotationally fixed manner to at least two support arms of the respective side section and a potentiometer assigned to the respective measuring shaft. According to this embodiment, support arm assemblies are formed, which are each connected to one another by a measuring shaft and together generate a signal by means of a potentiometer.This provides the ground guidance control system with exactly the number of signals needed to determine the positions of the side sections and the center section of the three-part attachment. Each section provides the control system with a left and right signal, with two measuring shafts per side section and center section, respectively, for a total of six measuring shafts.

[0024] In a specific operating mode of the belt cutting unit, in which the knife bar rests on the ground over the entire width of the belt cutting unit, the measuring shafts can detect the position of the respective support arm, which can be pivoted about the axis running transversely to the direction of travel, relative to the frame of the central section or the side sections.

[0025] The present invention is explained in more detail below with reference to an embodiment shown in the drawings.

[0026] They show: Fig. 1 schematically and exemplarily shows a partial view of a combine harvester with a front attachment arranged thereon; Fig. 2 schematically and exemplarily shows a partial view of a front attachment designed as a band cutter; and Fig. 3 a schematic and highly simplified representation of the segmented front attachment designed as a band cutter according to Fig. 2 .

[0027] In Fig. 1A schematic and exemplary partial view of a combine harvester 1 with an attachment 2 arranged thereon is shown. The attachment 2 is arranged on a receiving device 3. The receiving device 3 can be pivoted about a pivot axis 4 vertically to the direction of travel FR. The receiving device 3 can be pivoted about the pivot axis 4 running transversely to the direction of travel FR by at least one hydraulic cylinder 5, which is articulated at one end to a bracket 6 of the combine harvester 1 and at its piston rod end to the receiving device 3.

[0028] By means of two lifting cylinders 7, of which Fig. 1only one is visible, a transverse adjustment of the front attachment 2 to the current ground level is regulated, whereby in the present embodiment the lifting cylinders 7 can pivot the front attachment 2 in a manner known per se about a virtual pendulum axis 8 pointing in the direction of travel FR. A hydraulic cylinder 9 arranged on the upper side of the receiving device 3 makes it possible to set a cutting angle which is enclosed by the front attachment 2 and the ground 10.

[0029] The front attachment 2 comprises a cutter bar 11, which is guided at an adjustable distance 12 from the ground 10. The distance 12 is adjusted by the hydraulic cylinders 5. To monitor maintenance of the distance 12 from the ground, several sensors 13 are arranged on the underside of the front attachment 2. In the illustrated embodiment, the sensors 13 are designed as several sensing arms 14.1 to 14.8, each of which can be pivoted about a shaft 15 running transversely to the direction of travel FR. The pivoting movement of the respective sensing arm 14.1 to 14.8 is determined by means of a potentiometer 16, which is coupled to the respective shaft 15. A control device 17 is provided to control the combine harvester 1 and its working units, which include, among others, the front attachment 2 and the pickup device 3.

[0030] Fig. 2shows schematically and exemplarily a partial view of an attachment 2 designed as a belt cutting device 20. The structure of the attachment 2 designed as a belt cutting device 20 is mirror-symmetrical, so that the following explanations apply accordingly to the half of the belt cutting device 20 not shown. The belt cutting device 20 comprises a Fig. 2 half shown, central section 21 and at least two side sections 22L, 22R. Of the side sections 22L, 22R, Fig. 2only one is shown. The belt cutting unit 20 is arranged in the region of the central section 21 on the receiving device 3. To convey the picked-up crop, conveyor belts (not shown) are provided which, in a known manner, convey the crop from the side sections 22L, 22R sideways to the central section 21. The respective side section 22L, 22R is pivotally connected to the central section 21 by a frame joint 23 about a pivot axis 24 oriented parallel to the direction of travel FR and extending essentially horizontally. The respective side section 22L, 22R is pivotable in the vertical direction about the pivot axis 24 relative to the central section 21 by means of an actuator 25. The actuator 25, which is preferably designed as a hydraulic cylinder, is assigned a pressure sensor 33 by which the pressurization of the actuator 25 is detected in order to control this pressure by the control device 17.A sensor device, in particular designed as a potentiometer, is assigned to the respective pivot axis 24, which serves to determine the position of the respective side section 22L, 22R relative to the central section 21.

[0031] In the front area of ​​the attachment 2, designed as a belt cutting unit 20, a flexible cutter bar 26 is arranged, which extends essentially across the entire width of the belt cutting unit 20. A plurality of support arms 27, which are distributed across the width of the belt cutting unit 20 and are arranged with one end pivotable about an axis running transversely to the direction of travel FR on the frame 28 of the belt cutting unit 20, which is divided or segmented into the central section 21 and the at least two side sections 22L, 22R, support the cutter bar 26. Due to the individual pivotability of the support arms 27, the flexible cutter bar 26 can execute a compensating movement in the vertical direction in order to react to a change in the ground contour. In this case, the cutter bar 26 can experience an essentially wave-like deflection.

[0032] The support arms 27 of the central section 21, arranged on both sides adjacent to the receiving device 3, are each connected to one another by a measuring shaft 29a, 29b, which is connected in a rotationally fixed manner to the respective support arms 27. At least one potentiometer 30 is arranged on the respective measuring shaft 29a, 29b, by which the vertical deflection of the support arms 27 connected to one another by the measuring shaft 29a, 29b is detected. The support arms 27 of the side sections 22 are also connected to one another by measuring shafts 31a, 31b, which are connected in a rotationally fixed manner to the respective support arm 27. Here and preferably, at least two measuring shafts 31a, 31b or 32a, 32b are provided on each side section 22, of which the measuring shaft 31a or 32a, starting from the central section 21, couples two or more support arms 27 to one another for measurement purposes. The measuring shaft 31b or 32b couples two or more support arms 27 together for measurement purposes, starting from the outer end region of the side section 22L, 22R.

[0033] At least one potentiometer 30 is also arranged on the respective measuring shaft 31a, 31b, 32a, 32b. The measuring shafts 29a, 29b, 31a, 31b, 32a, 32b and the associated potentiometers 30 also form sensors 13, with which a vertical distance 12 of the belt cutting unit 20 from the ground 10 is determined in a manner known per se. In a specific operating mode of the belt cutting unit 20, in which the cutter bar 26 rests on the ground 10 across the entire width of the belt cutting unit 20, the measuring shafts 29a, 29b, 31a, 31b, 32a, 32b detect the position of the respective support arm 27, which can be pivoted about the axis running transversely to the direction of travel FR, relative to the frame 28 of the central section 21 or the side sections 22R, 22L. The segmented frame 28 is guided to a desired position relative to the support arms 27 by raising and lowering the receiving device 3, while the cutter bar 26 follows the ground contour.When operating in this specific operating mode of the belt cutting unit 20, the distance of the segmented frame 28 to the ground 10 is determined for each frame segment by means of the measuring shafts 29a, 29b, 31a, 31b, 32a, 32b.

[0034] Due to the rotationally fixed connection of the support arms 27 to the respective measuring shafts 29a, 29b, 31a, 31b, 32a, 32b, the deflection of the support arms 27 is detected by a deflection in the vertical direction due to the soil contour. The signals from the measuring shafts 29a, 29b, 31a, 31b, 32a, 32b are evaluated by the control device 17 of the combine harvester 1, analogous to the signals from the sensors 13 designed as sensing arms 14.1 to 14.8.

[0035] The representation in Fig. 3 shows a schematic and highly simplified representation of the segmented attachment 3 designed as a band cutting device 20 according to Fig. 2For the sake of simplicity, the illustration also shows the arrangement of the sensors 13, which can be either sensing arms 14.1 to 14.8 or measuring shafts 29a, 29b, 31a, 31b, 32a, 32b. The basic procedure by which the positioning of the side sections 22L, 22R relative to the central section 21 is controlled or regulated for ground guidance of the front attachment 2, independent of the height and lateral guidance of the front attachment 2 controlled by the combine harvester 1, does not differ. Only the type and / or number of sensors 13 can vary.

[0036] The actuators 25, which pivot the respective side sections 22L, 22R relative to the center section 21 about the pivot axis 24, are symbolically indicated by arrows. This applies correspondingly to the symbolic representation of the frame joints 23 and the pivot axes 24 between the center section 21 and the side sections 22.

[0037] The side sections 22L, 22R are controlled or regulated taking into account a selectable operating mode for ground guidance of the front attachment 2. The operating modes can be selected from the group "cutting height control," "ground pressure control," and "cutting height preselection." One of the operating modes can be selected using an operator terminal or another input / output unit 18 connected to the control device 17 of the combine harvester 1.

[0038] With cutting height control as the operating mode for ground guidance, the distance 12 of the front attachment 3 relative to the ground 10 is specified by entering at least one target value. With ground pressure control as the operating mode for ground guidance, ground guidance is based on a preset ground pressure by placing the front attachment 3 on the ground 10 with a weight proportion of the total weight of the front attachment 3 specified as the target value. The ground pressure exerted on the ground 10 is adjusted by controlling at least one hydraulic cylinder 5 on the pickup device 3. With cutting height preselection as the operating mode for ground guidance, an angle of inclination 19 by which the pickup device 3 is pivoted relative to the combine harvester 1 about the horizontally extending pivot axis 4 is set to a predetermined target value for the position of the pickup device 3 relative to the ground 10.

[0039] In the "cutting height control" operating mode, the position of the respective side section 22R, 22L relative to the central section 21 is controlled as a function of a distance difference ΔT R or ΔT L of a distance A1R, A1L detected at the outer end of the respective side section 22L, 22R to the ground 10 and a distance A2R, A2L detected in the area of ​​the pivot axis 24 to the ground 10 by controlling the actuator 25 until the respective distance difference ΔT R or ΔT L of the side sections 22R, 22L is zero.

[0040] For this purpose, the distance difference ΔT R or the distance difference ΔT L of the respective side section 22R, 22L in the case of sensors 13 designed as sensing brackets 14.1 to 14.8 is determined as follows: Δ T R = min 14.1 , 14.2 − min 14.3 14.4 and Δ T L = min 14.7 , 14.8 − min 14.5 14.6 .

[0041] The minimum value detected by sensors 14.1, 14.2, 14.7, 14.8, and 14.3, 14.4, 14.5, 14.6 for a distance A1R, A1L or A2R, A2L is used. The goal of the control is to ensure that the distance difference ΔT R or ΔT L of the side sections 22R, 22L is zero.

[0042] In the case of measuring shafts 29a, 29b, 31a, 1b, 32a, 32b as sensors 13, distance differences ΔF R or ΔF L are determined by evaluating distances of a respective side section 22R, 22L measured at several points on the respective side section 22R, 22L, unlike the use of sensing arms 14.1 to 14.8, which measure pointwise due to their specific arrangement. The measuring shafts 31b, 32b measure the distance A1R, A1L at the outer ends of the side sections 22R, 22L, while the measuring shafts 31a, 32a measure a value for the distance A2R, A2L in the area of ​​the pivot axis 24. 22L. The measuring shafts 29a, 29a at the central section 21 also measure a value for the distance A2R, A2L.

[0043] The determination of the distance difference ΔFR at side section 22R is explained as an example. The following explanations apply accordingly to side section 22L.

[0044] A distance difference ΔF R,MA is determined from the determined distance values ​​of the measuring shafts 31b and 31a of the side section 22R, a distance difference ΔF R,IM is determined from the determined distance values ​​of the measuring shaft 31a on the side section 22R and the measuring shaft 29a on the middle section 21, and a distance difference ΔF R,IA is determined from the determined distance values ​​of the measuring shaft 29a on the middle section 21 and the measuring shaft 31b on the side section 22R. As with the control with the sensing arms 14.1 to 14.8, the objective is that the distance difference ΔF R or ΔF L is controlled to the value zero by controlling the actuators 25 by the control device 17.

[0045] The distance difference ΔF R is determined as follows: Δ F R = Δ F R , IA f ü r Δ F R , MA > Δ F R , IM − Δ F R , IA f ü r Δ F R , MA ≤ Δ F R , IM .

[0046] In the "ground pressure control" operating mode, the attachment 2 is placed on the ground 10 with a preset weight percentage of the total weight as the target value. The weight percentage is adjusted by applying pressure to at least one hydraulic cylinder 5. To control the positioning of the respective side section 22R, 22L, the actuator 25 is controlled depending on the target value and the partial weight of the respective side section 22R, 22L, so that the respective side section 22R, 22L is placed on the ground 10 with its corresponding partial weight percentage. The independent positioning of the side sections 22R, 22L can be achieved with the actuators 25 designed as hydraulic cylinders based on the pressure in the respective hydraulic cylinder between the central section 21 and the respective side section 22R, 22L.The control device 17 can regulate the pressure in the respective hydraulic cylinder based on the partial weight of the respective side section 22R, 22L with which the respective side section 22R, 22L is to be placed on the ground 10.

[0047] In the "cutting height preselection" operating mode, the angle of inclination 19 between the pickup device 3 and the combine harvester 1 is preset to specify a cutting height target value. It is provided that, for positioning the respective side section 22R, 22L, it is detected whether at least one of the sensors 13 of the respective side section 22R, 22L is in contact with the ground 10 when the cutting height target value is set. This allows different operating situations to be recorded in which the front attachment 2 can be operated. Thus, in an operating situation in the "cutting height preselection" operating mode, the front attachment 2 can be raised by the pickup device 3 to such an extent that none of the sensors 13 contact the ground or, in the case of the sensors 13 designed as measuring shafts 29a, 29b, 31a, 31b, 32a, 32b, detect contact with the ground. This could be the case, for example, with a high cut.In an alternative operating situation in the "cutting height preselection" operating mode, the cutting height setpoint is selected such that the front attachment 2 is so close to the ground 10 that at least one sensor 13 has or detects ground contact.

[0048] If it is detected that all sensors 13 are not in contact with the ground, the respective side section 22R, 22L can be moved into a central position by controlling the respective actuator 25, in which the respective side section 22R, 22L is positioned substantially flush with the central section 21. The signals of the sensor device assigned to the respective pivot axis 24 are used for control.

[0049] However, if at least one of the sensors 13 is detected to be in contact with the ground, the positioning of the respective side section 22R, 22L is carried out according to the "cutting height control" operating mode. This prevents a collision of the respective side section 22R, 22L with the ground 10 in the "cutting height preselection" operating mode.

[0050] In particular, during operation without selecting an operating mode, the positioning of the respective side sections 22R, 22L can be performed according to the "cutting height preselection" operating mode. During operation without selecting an operating mode, the current travel speed of the combine harvester 1 or the manual raising or lowering of the front attachment 2 are monitored. If the travel speed of the combine harvester 1 exceeds a threshold value, for example, 2 km / h, or if the front attachment 2 is manually raised, the positioning of the side sections 22R, 22L is performed analogously to the "cutting height preselection" operating mode to ensure that the side sections 22R, 22L are only moved relative to the central section 21 when no persons are present in the area of ​​the side sections 22R, 22L. List of reference symbols 1 Combine harvester 26 knife bar 2 Attachment 27 Support arm 3 Recording device 28 Frame 4 Swivel axis 29a measuring shaft 5 hydraulic cylinder 29b measuring shaft 6 console 30 potentiometer 7 lifting cylinder 31A measuring shaft 8 Swing axle 31B measuring shaft 9 hydraulic cylinder 32A measuring shaft 10 Floor 32B measuring shaft 11 knife bar 33 pressure sensor 12 Distance A1L Distance 13 sensor A1R Distance 14.1 Touch bar A2L Distance 142 Touch bar A2R Distance 14.3 Touch bar FR Direction of travel 14.4 Touch bar 14.5 Touch bar 14.6 Touch bar 14.7 Touch bar 14.8 Touch bar 15 Wave 16 potentiometer 17 Control device 18 Input-output unit 19 Angle of inclination 20 Belt cutting unit 21 Middle section 22R Page section 22L Page section 23 frame joint 24 Swivel axis 25 Actuator

Claims

1. A method for operating a front attachment (2, 20) disposed on a pick-up device (3) of a self-propelled combine harvester (1), wherein the front attachment (2, 20) comprises a centre section (21) and two side sections (22R, 22L) which are respectively pivotably connected to the centre section (21) about a pivot axis (24) orientated in the direction of travel (FR) by a frame joint (23), wherein the respective side section (22R, 22L) is pivotable about the pivot axis (24) relative to the centre section (21) transversely to the direction of travel (FR) by means of an actuator (25) which is controlled by a control device (17), wherein a vertical distance (12) of the front attachment (2) from the ground is adaptively set by at least one hydraulic cylinder (5) on the pick-up device (3), wherein, for the ground guidance of the front attachment (2), the positioning of the side sections (22R, 22L) relative to the centre section (21) is controlled or regulated independently of vertical and transverse guidance of the front attachment (2) controlled by the combine harvester (1), characterized in that the side sections (22R, 22L) are controlled or regulated taking into account a selectable operational mode for the ground guidance of the front attachment (2, 20), wherein the operational modes are selected from the "cutting height regulation", "ground pressure regulation" and "cutting height preselection" group.

2. The method according to claim 1, characterized in that the positioning of the side sections (22R, 22L) is carried out independently of one another by the respective actuator (25).

3. The method according to one of claims 1 and 2, characterized in that measurement signals from at least two sensors (13) respectively disposed in a manner spaced apart from one another on the respective side section (22R, 22L) and the centre section (21) are received and evaluated by the control device (17), from which measurement signals a respective distance (A1R, A2R, A1L, A2L) of the side sections (22R, 22L) and of the centre section (21) from the ground (10) are determined.

4. The method according to one of the preceding claims, characterized in that, in the "cutting height regulation" operational mode, the position of the respective side section (22R, 22L) relative to the centre section (21) is regulated as a function of a difference in distance (ΔTR, ΔTL; ΔFR, ΔFL) between a distance (A1R, A1L) from the ground (10) detected at the outer end of the side section (22R, 22L) and a distance (A2R, A2L) from the ground (10) detected in the region of the pivot axis (24), in which the actuator (25) is controlled until the difference (ΔTR, ΔTL; ΔFR, ΔFL) in distance is zero.

5. The method according to one of claims 1 to 4, characterized in that, in the "ground pressure regulation" operational mode, the front attachment (2, 20) is placed on the ground (10) with a preset proportion by weight of the total weight as the nominal value, which is set by pressurization of the at least one hydraulic cylinder (5), and in that, in order to regulate the positioning of the respective side section (22R, 22L), the actuator (25) is controlled as a function of the nominal value and of the part weight of the respective side section (22R, 22L) in a manner such that the respective side section (22R, 22L) is placed on the ground (10) with its corresponding proportion of the part weight.

6. The method according to one of claims 1 to 5, characterized in that, in the "cutting height preselection" operational mode, an angle of inclination (19) between the pick-up device (3) and the combine harvester (1) is preset in order to specify a nominal value for the cutting height, and in that, in order to position the respective side section (22R, 22L), detection is carried out as to whether at least one of the sensors (13) of the respective side section (22R, 22L) exhibits or detects a contact with the ground (10) in the case of the set cutting height nominal value.

7. The method according to claim 6, characterized in that in the case of a detection that none of the sensors (13) is in contact with the ground (10), the respective side section (22R, 22L) is transferred into a central position by control of the respective actuator (25), in which central position the respective side section (22R, 22L) is positioned so as to be substantially in alignment with the centre section (21).

8. The method according to claim 6, characterized in that in the case of a detection that at least one of the sensors (13) exhibits or detects a contact with the ground (10), the positioning of the respective side section (22R, 22L) is carried out in accordance with the "cutting height regulation" operational mode.

9. The method according to one of claims 1 to 8, characterized in that, in the case of an operation without selection of an operational mode, the positioning of the respective side section (22R, 22L) is carried out in accordance with the "cutting height preselection" operational mode.

10. The method according to one of the preceding claims, characterized in that, in order to determine the position of a respective side section (22R, 22L) relative to the centre section (21), the difference between a distance (A1R, A1L) from the ground (10) detected by at least one sensor (13) at the outer end of the side section (22R, 22L) and a distance (A2R, A2L) from the ground (10) detected by at least one sensor (13) in the region of the pivot axis (24) is determined.

11. The method according to claim 10, characterized in that, in the region of the pivot axis (24), in order to determine the distance (A2R, A2L) from the ground (10), measurement signals are evaluated from a sensor (13) which is adjacent to the pivot axis (24) respectively disposed on the centre section (21) and on the side section (22R, 22L).

12. A self-propelled combine harvester (1) with a segmented front attachment (2), in particular a draper cutting unit (20), and a control device (17) which is configured for carrying out the method according to one of the preceding claims.

13. The self-propelled combine harvester (1) according to claim 12, characterized in that, in order to detect a distance (A1R, A1L, A2R, A2L) from the ground (10), sensors (13) which are configured as sensor arms (14.1 to 14.8) are disposed on the underside of the front attachment (2).

14. The self-propelled combine harvester (1) according to claim 12, characterized in that support arms (27) which are pivotable about an axis extending in the transverse direction and which carry a cutter bar (26) are disposed on the centre section (21) and on the side sections (22R, 22L), wherein, in order to detect a vertical deflection of the support arms (27) of the centre section (21) and of the side sections (22R, 22L), two sensors (13) are respectively provided, wherein the two sensors (13) of the centre section (21) are respectively constructed as a measuring shaft (29a, 29b) connected, in a manner which is fixed against rotation, to at least one of the support arms (27) of the centre section (21) and the two sensors (13) of the side sections (22R, 22L) are respectively constructed as a measuring shaft (31a, 31b, 32a, 32b) connected, in a manner which is fixed against rotation, to at least two support arms (27) of the respective side section (22R, 22L), and a potentiometer (30) associated with the respective measuring shaft (29a, 29b, 31a, 31b, 32a, 32b).