SELF-PROPELLED HARVESTING MACHINE WITH A HEIGHT-ADJUSTABLE PICKUP DEVICE

Description

[0001] The present invention relates to a self-propelled harvesting machine with a height-adjustable receiving device according to the preamble of claim 1.

[0002] From WO 2020 / 185873 A1, a self-propelled harvesting machine with a height-adjustable intake device is known. A front attachment for collecting crops is mounted on this device and pivots about a virtual pendulum axis of the intake device. The front attachment is pivotable about this virtual pendulum axis by means of one or more hydraulic cylinders, which are controlled by a control device of the harvesting machine and are mounted on the intake device. With front attachments that have a very large working width, particularly more than 12 m in total width, and / or a very high dead weight, pivoting the front attachment across its entire working width to adapt to a changing ground contour in the lateral direction leads to an unintended excitation of the harvesting machine.

[0003] A self-propelled harvesting machine with a height-adjustable intake device, on which a front attachment for collecting crops is mounted and pivotable about a virtual pendulum axis of the intake device, is known from DE 10 2020 110 574 A1. The intake device is designed for adaptive adjustment of the vertical distance of the front attachment to the ground by means of two hydraulic cylinders, each supported at its end against the frame of the harvesting machine, which allow the intake device and the front attachment mounted thereon to be positioned at different vertical distances. At least one support wheel is arranged at each of the outer lateral areas of the front attachment, each of which is guided vertically by a hydraulic cylinder connected to a hydraulic circuit of a hydraulic system having a pressure source.The support wheels are pivotally connected to a frame component of the header, with the support wheels located at the rear of the header, i.e., the rear of the header facing the pickup device. The support wheels act as gauge wheels for ground guidance of the header. The support wheels are extended according to a vertical distance specified by the operator of the harvesting machine until ground contact is made. In this position, the hydraulic cylinders of the support wheels are locked to ensure a constant working height when guiding the header across the field. The header known from DE 10 2020 110 574 A1 is designed to respond to changes in the vertical distance setting made by the operator by actuating the hydraulic cylinders of the support wheels, retracting or extending both of them.

[0004] With this header design, the header's position is only adjusted to a change in ground contour detected by the gauge wheels after the header has already passed the change in ground contour. The distance of the front section of the header, where the crop is picked up, is not optimally adjusted when the ground contour changes. Furthermore, it cannot be guaranteed that the gauge wheels or support wheels maintain constant ground contact, for example, if the underside of the header rests on the ground due to a change in ground contour. This leads to significant fluctuations in the load on the gauge wheels and the underside of the header, especially when the header is equipped with ground pressure control, where a certain percentage of its total weight rests on the ground.

[0005] Based on the aforementioned prior art, the invention is based on the objective of further developing a self-propelled harvesting machine of the aforementioned type, which is characterized by improved tracking of the header when adapting to a changed ground contour, in particular that the mean distance between the front area of ​​the header and the ground is essentially the same on average and that the force with which the support wheels bear against the ground is kept essentially constant on average.

[0006] This problem is solved from a device engineering perspective, starting from the preamble of claim 1 in conjunction with its characterizing features. The subsequent dependent claims describe advantageous embodiments of the invention.

[0007] According to the invention, a self-propelled harvesting machine is proposed with a height-adjustable receiving device on which a front attachment for receiving crops is arranged, pivotable about a virtual pendulum axis of the receiving device. The receiving device is configured for adaptively adjusting the vertical distance of the front attachment to the ground, and at least one support wheel is arranged at each of the outer lateral areas of the front attachment, each of which is guided vertically by a hydraulic cylinder connected to a hydraulic circuit of a hydraulic system having a pressure source. According to the invention, the position of the front attachment is controlled laterally by pivoting about the virtual pendulum axis, independently of at least one actuator for lateral guidance of the front attachment, which is controlled by the harvesting machine.The essential principle is that the attachment, during its operation or harvesting, pivots around the virtual pendulum axis in a transverse direction, independent of the control of at least one actuator on the receiving device, in order to compensate for irregularities in the ground contour that would lead to a one-sided change in a preset cutting height.

[0008] The at least one actuator arranged on the receiving device can be controlled to move it into a float position. The actuator used for active lateral guidance by the harvesting machine's control system is switched to neutral, so that the header is independent of the lateral guidance of the header controlled or regulated by the harvesting machine via the at least one actuator.

[0009] The position of the attachment is controlled transversely to the direction of travel by means of the support wheel located on the respective lateral section. The pressure applied to the hydraulic cylinders can be adjusted alternately to compensate for any deviation from the target lateral position of the attachment. The target lateral position corresponds, with respect to the entire working width of the attachment, to a minimum vertical distance between the front of the attachment and the ground, at which the hydraulic forces acting on the support wheels are essentially equal.The actual lateral position, again referring to the entire working width of the attachment, describes a deviation in the actual vertical distance of the front of the attachment to the ground caused by a change in the ground contour. This deviation must be compensated for by a relative deflection of the attachment around the virtual pivot axis of the mounting device. Pressure control allows a valve arrangement assigned to each hydraulic cylinder to be actuated in such a way that one hydraulic cylinder is subjected to lower pressure (i.e., relieved of load), while the other hydraulic cylinder is subjected to higher pressure (i.e., more heavily loaded) by the other valve arrangement. This allows the attachment to be pivoted alternately to the left or right. Once the adjustment of the actual lateral position to the target lateral position is complete, both hydraulic cylinders are again continuously regulated.evenly subjected to pressure.

[0010] Preferably, the hydraulic cylinders of the support wheels can be designed as double-acting hydraulic cylinders.

[0011] According to a preferred embodiment, a control device can be provided which is configured for pressure-controlled actuation of a valve arrangement assigned to the respective hydraulic cylinder, wherein the valve arrangement is configured to regulate a hydraulic pressure supplied by the pressure source in the hydraulic cylinder depending on an operating mode of the attachment selected during operation. In particular, height control and ground pressure control can be provided as operating modes. With height control, a vertical working height above the ground is specified, at which the front section of the attachment must be guided above the ground, which corresponds to a pickup height for the crop to be harvested.For this purpose, hydraulic cylinders integrated into the mounting device are actuated, pivoting the mounting device and the attached header vertically around a transverse axis orthogonal to its virtual pivot axis. The harvester bears the total weight of the header. With ground pressure control, the header rests on the ground, thus achieving partial weight relief. While height control focuses on maintaining the average distance to the ground by adjusting the position laterally, ground pressure control aims for the most even possible pressure distribution on the ground to prevent, for example, the header from being pushed down. Pressure control ensures that the force with which the support wheels bear against the ground remains constant on average.

[0012] The control device can be configured to actuate the valve arrangement assigned to each hydraulic cylinder in such a way that one hydraulic cylinder is subjected to a lower pressure, i.e., relieved of load, while the other hydraulic cylinder is subjected to a higher pressure by the other valve arrangement, i.e., under greater load. The control device is configured to compensate for any deviation in the actual lateral position of the attachment from the target position by means of pressure regulation.

[0013] Another advantage of the pressure control system arises when raising the header from its working position during operation or harvesting to a position raised off the ground, where the support wheels are not in contact with the ground, for example, at the headland. The pressure control system extends the hydraulic cylinders further as the header is raised, so that the header remains supported on the ground initially. Only when the hydraulic cylinders reach their end stop can they retract, moving the support wheels from their working position to their transport position.

[0014] In particular, the control device can be arranged on the attachment device.

[0015] The control device can be configured for autonomous control of the valve arrangements. Independently of the harvesting machine, the control device can actuate the valve arrangements to adjust the header to changes in the lateral ground contour by pivoting around the virtual pendulum axis of the receiving device. The autonomously operating control device can actively control or regulate the lateral tracking of the header.

[0016] According to a preferred embodiment, the attachment can be assigned several independently operating sensor devices, which are configured to detect the distance between the attachment and the ground. In particular, the sensor devices are arranged at the smallest possible distance to the front of the attachment. This small distance to the front of the attachment enables earlier responses to changes in the ground contour that necessitate an adjustment of the attachment's lateral position.

[0017] In particular, each support wheel can be equipped with sensors designed to detect its position relative to the attachment and / or the set pressure in the respective hydraulic cylinder of the support wheels. Detecting the position relative to the attachment is important to ensure that the support wheels can pivot around their transverse axis when the attachment is moved from a working position to a transport position. In the transport position, the respective hydraulic cylinders can be fully retracted, allowing the support wheels to be positioned at maximum distance from the ground.

[0018] Preferably, the control device can be configured to evaluate signals from the sensor devices to determine the actual lateral position, in order to correct the actual lateral position, which deviates from the target lateral position of the attachment, by loading or unloading the respective support wheel, through opposing control of the valve arrangements when pressurizing the hydraulic cylinders.

[0019] The active control of the support wheels compensates for deviations from the target lateral position caused by changing ground contours as soon as these are detected by the sensors located at the front of the header. The distance between the front of the header and the ground is optimally maintained, which has a correspondingly positive effect on crop intake.

[0020] Continuous pressure control in the hydraulic cylinders of the support wheels ensures that the optimal position of the support wheels is always maintained, even when a required vertical working height above the ground is changed in height control mode. At the same time, the pressure control guarantees that the force with which the support wheels bear against the ground remains constant on average.

[0021] Furthermore, the control device can be configured to determine when the target transverse position has been reached based on the evaluation of the signals from the sensor devices and to continue controlling the valve arrangements according to the selected operating mode.

[0022] In particular, the sensor devices can be designed as tactile bars or as non-contact distance sensors.

[0023] According to a preferred embodiment, the attachment device can be designed as a belt cutting unit comprising a central section and at least two side sections, each of which is pivotably connected to the central section by a frame joint about a pivot axis running parallel to the longitudinal axis of the harvesting machine, wherein the respective side section can be pivoted relative to the central section about the pivot axis transverse to the direction of travel by means of an actuator.

[0024] In the attachment designed as a belt cutter, pivotable support arms can be arranged on the central section and the side sections about a transverse axis. These support arms carry a flexible cutter bar extending across the width of the belt cutter. To detect vertical deflection of the support arms of the central and side sections about the transverse axis, several sensor devices are provided. These sensor devices consist of a measuring shaft non-rotatably connected to the support arms of the central section and at least one measuring shaft non-rotatably connected to the support arms of each side section, with potentiometers attached to it. The respective measuring shaft is spaced apart from the flexible cutter bar by the support arms. In the belt cutter, the measuring shafts with the potentiometers attached to them can be used to determine the distance between the attachment and the ground.This is particularly the case when the belt cutter is operated in so-called flex mode. In this operating mode, the support arms carrying the flexible cutter bar can be deflected downwards and / or upwards, at least partially, even within a lateral section, starting from a horizontal center position, due to changes in the ground contour perpendicular to the direction of movement of the header carried by the harvester. The translational movement of the support arms generated by this deflection produces a rotational movement of the measuring shafts, which is detected by the potentiometers arranged on the measuring shafts. The signal evaluation of the potentiometers is analogous to the signal evaluation of sensor devices designed as probes.

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

[0026] They show: Fig. 1 schematically and by way of example a front structure of a self-propelled harvesting machine; Fig. 2 a front view of a receiving device of the harvesting machine; Fig. 3 an exemplary circuit diagram for the control of support wheels of the header; and Fig. 4 schematically and by way of example a partial view of a header designed as a belt cutter.

[0027] The representation in Fig. 1Figure 1 shows the basic front structure of a self-propelled harvesting machine 1, designed as a combine harvester 2, with a header 3, which in the illustrated embodiment is designed as a grain header 4. The header 3 is mounted on a machine frame 5 of the harvesting machine 1 by means of a receiving device 6, designed as an inclined conveyor 16. The terms receiving device 6 and inclined conveyor 16 are used synonymously below. The receiving device 6 is pivotally mounted on the machine housing 5 about a pivot axis extending transversely to the forward direction FR of travel of the harvesting machine 1. The inclined conveyor 16 conveys the harvested crop 7 to a threshing unit (not shown) as a working unit of the harvesting machine 1. The header 3 has a cutter bar 8 and a transverse conveyor 9, which serve to transport the harvested crop 7 in front of the inlet opening of the inclined conveyor 16.The machine housing 5 is rigidly connected to a front axle 10 of the harvester 1. The wheels 11 are mounted on the front axle 10 in a height-adjustable manner, allowing for horizontal alignment of the components housed in the machine housing 5 for harvesting on slopes. For this purpose, the harvester 1 is equipped with two wheel drives 13, which are pivotably connected to the ends of the front axle 10 via brackets KS. Piston cylinder units 14 are supported on the brackets KS, and their piston rods engage the wheel drives 13, which in turn are pivotable about fixed axes 15 in the brackets KS. A longitudinal axis of the harvester 1 is designated by 12.

[0028] The receiving device 6 and the attachment 3 arranged on the receiving device 6 are raised and lowered by piston-cylinder units 17, which are attached at one end to the underside of the receiving device 6 and at the other end in the area of ​​the front axle 10. The attachment 3 is coupled via a pivoting device 18. Such a pivoting device 18 is disclosed in DE 10 2019 111 587 A1, to which full reference is made. The pivoting device 18 consists of a frame structure 19 on the attachment side, designed as a pendulum frame 18a, and a frame structure 20 on the harvester side, designed as a tilting frame 18b. The pendulum frame 18a is pivotably mounted relative to the tilting frame 18b about a virtual pendulum axis 21 extending approximately in the forward direction VR, and allows the attachment 3 to pivot relative to the receiving device 6 about the virtual pendulum axis 21.The virtual pendulum axis 21 is formed at the center of the pendulum frame 18a. The tilting frame 18b is pivotably mounted on the receiving device 6 with a piston-cylinder unit 22 about a lower transverse axis 23, so that a cutting angle of the attachment 3 can be adjusted in the longitudinal direction of the machine.

[0029] In Fig. 2Figure 1 shows a front view of the receiving device 6 of the harvesting machine 1. The tilting frame 18b holds two support rollers 20a in its upper region, which are rotatable about their axes 20b extending parallel to the direction of the virtual oscillation axis 21. A support element 20c rests on the support rollers 20a, extending along a circular path 20d, which is arranged concentrically to the virtual oscillation axis 21 and is connected to the oscillation frame 18a. The described arrangement of the support rollers 20a enables the oscillation frame 18a to oscillate about the virtual oscillation axis 21. In the illustrated embodiment, two support rollers 20a are mounted on the tilting frame 18b symmetrically to the longitudinal center plane of the tilting frame 18b on a circular path 20e extending concentrically to the virtual oscillation axis 21.

[0030] To actively pivot the header 3 about the pendulum axis 21, an actuator 22a, designed as a pivot cylinder, is mounted between the pendulum frames 18a and the tipping frames 18b. This allows the pivot cylinder 22a to actively pivot the pendulum frame 18a relative to the tipping frames 18b about the virtual pendulum axis 21. During operation, the actuator is in a floating position, so that the header 3 is freely suspended from the harvesting vehicle 1. For the active pivoting of the header 3, the pivot cylinder 22a is controlled by a control unit of the combine harvester 2 at the mounting device 6. This actuation moves and holds the header 3 in a horizontal position in the raised position, where the support wheels 24 on the header are not in contact with the ground.

[0031] A necessary lateral compensation, which involves pivoting the attachment 3 about the virtual pendulum axis 21 to adapt its position to changing ground contours, is achieved during operation or harvesting by means of two height-adjustable support wheels 24. In the exemplary embodiment, two brackets 25 are pivotably attached to the attachment 3 about an axis 26 extending transversely to the forward direction of travel FR. The brackets 25 are mounted in the outer lateral area of ​​the attachment 3 and arranged symmetrically to the longitudinal center plane of the attachment 3, which in the exemplary embodiment corresponds to the longitudinal center plane of the pendulum frame 18a. Each bracket 25 is pivoted by means of a hydraulic cylinder 27, which is attached to both the attachment 3 and the bracket 25.The hydraulic cylinders 27, which are designed as double-acting hydraulic cylinders, are controlled in the exemplary embodiment by means of sensor devices 28. These devices continuously measure the distance 29 between the cutter bar 8 (the front area of ​​the attachment 3) and the ground 30 in a manner known per se. In the illustrated exemplary embodiment, the sensor devices 28 are pivotally movable sensing arms 31. The sensing arms 31 are arranged on the underside of the attachment 4. The distance between the sensing arms 31 and the cutter bar 8 is chosen to be as small as possible in order to react to changes in the ground contour at an early stage. Alternatively, the sensor devices 28 can operate without contact. The support wheels 24 are rotatably mounted on the bracket 25 about an axis 32 extending transversely to the forward direction of travel VR.Depending on the operating mode selected for the attachment 3, the support wheels 24 are guided over the ground 30 during operation and controlled on the basis of the sensor signals of the sensor devices 28 in such a way that the position of the attachment 3 is adapted to existing ground contours.

[0032] One operating mode is the cutting height control, in which the distance 29 of the cutter bar 8 to the ground 30 to be maintained is specified and is set by controlling the piston cylinder units 17.

[0033] Another operating mode is the so-called ground pressure control. In ground pressure control mode, the attachment 3 rests on the ground 30, so that the weight of the attachment 3 is partially transferred to the ground.

[0034] In Fig. 3An exemplary circuit diagram for controlling the support wheels 24 of the attachment 3 is shown. A hydraulic system 33 is provided on the attachment 3 to control the externally arranged support wheels 24. This system comprises a common pressure source 34 and a common tank 35. The hydraulic system 33 is designed as a mirror image for the laterally opposite support wheels 24 of the attachment 3, so that the following description of the other components of the hydraulic system 33 applies to both support wheels 24 arranged laterally on the attachment 3. Each hydraulic cylinder 27 is assigned a valve arrangement VL, VR, which is explained below.

[0035] From the common pressure source 34, which can be a hydraulic pump of the self-propelled harvester 1, a pressure line 36 leads to a switchable valve 37 designed as a 3 / 2-way proportional valve and an optional downstream 2 / 2-way valve 38, which is designed as a single-lever seal. The optional 2 / 2-way valve 38 prevents leakage of hydraulic fluid through the switchable valve 37. As shown in Fig. 5, the switchable valve 37 can assume a switching state in which the pressure line 36 is connected to the tank 35 via a hydraulic line 39. The 2 / 2-way valve 38 is in a switching position in which the flow of hydraulic fluid from the pressure line 36 through the switchable valve 37 into the tank 35 is prevented.

[0036] A pressure sensor 40, located downstream of the switchable valve 37 (designed as a 3 / 2-way proportional valve) or the 2 / 2-way valve 38, monitors the hydraulic pressure in the pressure line 36. A throttle check valve 41 with a pressure accumulator 42 is assigned to each hydraulic cylinder 27 and is located in the pressure line 36 connecting the common pressure source 34 of the hydraulic system 33 with the hydraulic cylinder 27.

[0037] Furthermore, a 3 / 2-way valve 43 is assigned to the hydraulic cylinder 27. During harvesting operation of the header 3, the valve, when energized, assumes a switching state in which the piston rod chamber 44 and piston chamber 45 of the hydraulic cylinder 27 are fluid-conductingly connected. This fluid-conducting connection between the piston rod chamber 44 and piston chamber 45 of the double-acting hydraulic cylinder 27 forms a common, closed hydraulic circuit 46. The respective hydraulic circuit 46 can be supplied by the pressure source 34. During operation of the header 3, i.e., during a harvesting process, the switching position of the 3 / 2-way valve 43, which fluid-conductingly connects the piston rod chamber 44 and the piston chamber 45, ensures that, as soon as the piston chamber 45 and piston rod chamber 46 are connected, the hydraulic cylinder 27 moves only due to external influences, in particular uneven ground.Hydraulic fluid displaced from the piston chamber 45 can flow into the pressure accumulator 42 via the 3 / 2-way valve 43. Depending on the cylinder movement, the differential volume is either drawn from or pushed back into the pressure accumulator 42. Alternatively, this can also be achieved by using two 2 / 2-way valves instead of the 3 / 2-way valve 43.

[0038] In the Fig. 3 In the illustrated switching position of the 3 / 2-way valve 43, the double-acting hydraulic cylinder 27 is actuated by switching valves 37 and 38 when pressure is applied, in order to move the respective support wheel 24 into a raised position, for example at the headland or for transport purposes. In the raised position, the support wheels 24 have no ground contact.

[0039] During harvesting operations, the 3 / 2-way valve 43 is in the switching position (not shown) in which the piston rod chamber 44 and the piston chamber 45 of the hydraulic cylinder 27 are fluidly connected. Pressure fluctuations due to shocks transmitted to the respective hydraulic cylinder 27 via the support wheels 24 flow through the 3 / 2-way valve 43 into the downstream pressure accumulator 42 and are compensated. For continuous pressure control of the respective hydraulic cylinder 27, the switchable valve 37 and the 2 / 2-way valve 38 of the valve assemblies VL and VR are controlled by a control device 50. The control device 50 is configured to control the valve assemblies VL and VR both simultaneously and independently of each other. During continuous pressure control, the pressures in the two hydraulic cylinders 27 are regulated to the same value.

[0040] Furthermore, the respective hydraulic cylinder 27 is controlled during harvesting operations by means of the switchable valve 37 and the 2 / 2-way valve 38 when, due to a change in the ground contour or reaching a slope, it is necessary to redirect the attachment 3 in the transverse direction QR by pivoting about the virtual pendulum axis 21 of the receiving device 6, which is explained in more detail below.

[0041] The piston chamber 45 is connected directly to the pressure line 36 via a compensating line 48, the switchable 3 / 2-way valve 43, and optionally via a check valve 49. The optional check valve 49, located in the compensating line 48, prevents hydraulic fluid from the pressure line 36 from entering the piston chamber 45 bypassing the 3 / 2-way valve 43.

[0042] In the illustrated switching position, the 3 / 2-way valve 43 connects the compensating line 48 to the tank 35 via the hydraulic line 47. In this switching position, the hydraulic cylinder 27 can be fully retracted to move the support wheel 24 into its transport position. The same applies to reaching a headland during harvesting: switching the 3 / 2-way valve 43 connects the piston chamber 45 to the tank 35 to raise the support wheel 24.

[0043] Here, and preferably, a control device 50 is provided, which is arranged on the attachment device 3. The control device 50 is configured to control the valve arrangement VL, VR assigned to the respective hydraulic cylinder 27, which each comprises the valves 37, 38 and 43, wherein the respective valve arrangement VL, VR is configured to regulate a hydraulic pressure provided by the pressure source 34 in the hydraulic cylinder 27 depending on a selected operating mode of the attachment device 3.

[0044] Sensors 51 and 52 are arranged on each hydraulic cylinder 27 to detect its position relative to the attachment 3 and / or the set pressure in the respective hydraulic cylinder 27 of the support wheels 24. The signals from sensors 51 and 52 are transmitted to the control device 50 for evaluation.

[0045] The control device 50 is specifically designed for the autonomous control of the valve arrangements VL, VR of the respective hydraulic cylinder 27. The control device 50 can actuate the respective valve arrangements VL, VR of the respective hydraulic cylinder 27 independently of the harvesting machine 1 in order to follow the header 3 when the ground contour changes in the transverse direction QR by freely pivoting about the virtual pendulum axis 21 of the receiving device 6. The autonomously operating control device 50 can actively control or regulate the tracking of the header 3 in the transverse direction QR by varying the deflection of the support wheels 24 through a change in the pressure applied to the respective hydraulic cylinder 27. For example, the pressure control actuates the valve arrangement VL in such a way that the corresponding hydraulic cylinder 27 is pressurized to a lower pressure, i.e.,The hydraulic cylinder 27 is relieved of pressure by a corresponding control of the valve assembly VR, while the hydraulic cylinder 27 is pressurized with higher pressure, i.e., subjected to a greater load. This causes the attachment 3 to pivot to the left. To pivot the attachment 3 to the right, the hydraulic cylinder 27 is relieved of pressure by a corresponding control of the valve assembly VR, and the hydraulic cylinder 27 is subjected to a corresponding load by a corresponding control of the valve assembly VL. Once the adjustment of the actual lateral position to a target lateral position is complete, both hydraulic cylinders are again continuously regulated, i.e., subjected to a uniform pressure.

[0046] Fig. 4Figure 53 schematically and exemplarily shows a partial view of an attachment 3 designed as a belt cutter 53. The belt cutter 53 is mirror-symmetrical in design, so the following descriptions apply accordingly to the half of the belt cutter 53 not shown. The belt cutter 53 comprises a central section 54 and at least two side sections 55, of which in Fig. 4Only one is shown. Conveyor belts (not shown) are provided for conveying the harvested crop, transporting it laterally from the side sections 55 to the central section 54 in a known manner. Each side section 55 is pivotably connected to the central section 54 by a frame joint 56 about a pivot axis 57 oriented parallel to the direction of travel FR and running essentially horizontally. Each side section 55 can be pivoted vertically about the pivot axis 57 relative to the central section 54 by means of an actuator 58.

[0047] In the front area of ​​the attachment 3, designed as a belt cutter 53, a flexible cutter bar 59 is arranged, extending essentially across the entire width of the belt cutter 53. A plurality of support arms 60, distributed across the width of the belt cutter 53, are pivotably mounted at one end on the frame 61 of the belt cutter 53, which is divided or segmented into the central section 54 and at least two side sections 55, supporting the cutter bar 59. The pivotability of the support arms 60 allows the flexible cutter bar 59 to perform a compensating movement in the vertical direction to respond to changes in the ground contour. In doing so, the cutter bar 59 can exhibit a substantially undulating deflection.

[0048] The support arms 60 of the central section 54 are connected to each other by a measuring shaft 62, which is rotationally fixed to the respective support arm 60. At least one potentiometer 63 is arranged on the measuring shaft 62, by which the vertical deflection of the support arms 60 connected to each other by the measuring shaft 62 is detected. The support arms 60 of the side sections 55 are also connected to each other by at least one measuring shaft 64, which is rotationally fixed to the respective support arm 60. Here, and preferably, at least two measuring shafts 64 are provided on each side section 55. At least one potentiometer 63 is also arranged on each measuring shaft 64. The measuring shafts 62, 64 and the associated potentiometers 63 also form sensor arrangements 28, with which the distance 29 of the cutter bar 59, as the front area of ​​the belt cutter 53, and the ground 30 is continuously measured in a manner known per se.

[0049] Each measuring shaft 64 connects only a portion of the support arms 60 of the respective side section 55, thus increasing the number of measuring points across the width of the belt cutter 53. Due to the rotationally fixed connection of the support arms 60 to the respective measuring shaft 62, 64, the deflection of the support arm 60 with the greatest vertical deflection due to the ground contour is used to determine the height position. The signals from the measuring shafts 62, 64 are evaluated by the control device 50 on the attachment 3, analogous to the signals from the sensor devices 28 designed as probe arms 31, and are used to control the valve arrangements VL, VR and the pressure regulation of the hydraulic cylinders 27, respectively.

[0050] As explained above, the side sections 55 can be pivoted by the actuators 58 about the pivot axis 57 transversely to the direction of travel FR, i.e., in the transverse direction QR. The entire belt cutter 53 is supported against the ground 30 by the laterally arranged support wheels 24. The belt cutter 53 is equipped with the hydraulic system 33 already described, similar to the grain cutter 4 mentioned earlier.

[0051] The pressure-controlled position regulation of the attachment 3 or the belt cutter 53 in the transverse direction QR is achieved by means of the laterally arranged support wheels 24, which are alternately depressurized or compressed to compensate for any deviation of the actual transverse position of the attachment 3 or the belt cutter 53 from the target transverse position. This regulation is intended to optimally maintain the cutting height specified by the piston cylinder unit 17, i.e., the distance 29 between the cutter bar 8 or 59 and the ground 30. Likewise, the pressure in the hydraulic cylinders 27, with which the support wheels 24 are pressed against the ground 30, is to be kept constant on average.

[0052] For this purpose, the control device 50 is provided, which is configured to control the valve arrangement VL, VR assigned to the respective hydraulic cylinder 27. The respective valve arrangement VL, VR is configured to regulate the hydraulic pressure in the hydraulic cylinder 27, supplied by the pressure source 34, depending on the selected operating mode, the cutting height control, the ground pressure control, and, in the case of the belt cutter 53, the flexible control of the cutter bar 59, according to which the cutter bar 59 of the belt cutter 53 follows the ground contour by means of the pivoting support arms 60. By controlling the respective valve arrangement VL, VR, the support wheels 24 can be actuated in opposite directions and extended and retracted independently of each other.

[0053] When the attachment 3 is lowered into its working position, which is determined by the selected operating mode, the support wheels 24 are extended under pressure control. The pressures in the hydraulic cylinders 27 of the support wheels, which rest on the ground 30, are continuously regulated during operation. Pressure monitoring is performed by the sensors 52 of the respective hydraulic cylinder 27. If the evaluation of the signals from the sensor arrays 28 indicates that the actual lateral position of the attachment 3 needs to be adjusted, for example, upon reaching a slope, the hydraulic cylinders 27 of the support wheels 24 are alternately relieved of pressure, thus achieving the required adjustment to the target lateral position.For this purpose, when the attachment 3 needs to be pivoted to the left, the left support wheel 24 is relieved of pressure by actuating the valve assembly VL, thus reducing the pressure force applied to the support wheel 24 by the hydraulic cylinder 27. Simultaneously, the right support wheel 24 is additionally loaded by actuating the valve assembly VR, thereby increasing the pressure force applied to the support wheel 24 by the hydraulic cylinder 27. Once the desired lateral position is reached, the pressures in the hydraulic cylinder 27 are again continuously regulated, i.e., by uniform pressure application.

[0054] When the attachment 3 is raised, for example at the headland, the pressures in the hydraulic cylinders 27 continue to be pressure-regulated. This causes the hydraulic cylinders to extend further until they reach their end position. Once the end position is reached, the hydraulic cylinders 27 are retracted under pressure control.

[0055] The harvesting machine according to the invention makes it possible to control the lateral position of the header 3, regardless of whether it is designed as a rigid grain cutter 4 or as a flexible belt cutter 53, and independently of the at least one actuator 22a, designed as a pivot cylinder and located on the receiving device 6, which is controlled by the harvesting machine 1 and serves to guide the header 3 laterally. During operation or harvesting of the header 3, the control of the lateral guidance is carried out exclusively by means of the pressure-controlled hydraulic cylinders 27 of the support wheels 24. Reference symbol list 1 Harvesting machine 26 axis 2 combine harvester 27 hydraulic cylinder 3 attachment 28 Sensor device 4 Grain cutter 29 Distance 5 machine frame 30 Floor 6 Recording device 31 Tactile bar 7 Harvested crops 32 axis 8 Knife bar 33 hydraulic system 9 Cross conveyor 34 Pressure source 10 front axle 35 tank 11 wheels 36 Pressure line 12 Longitudinal axis 37 valve 13 Wheel gear 38 2 / 2-way valve 14 Piston cylinder unit 39 hydraulic line 15 axis 40 Pressure sensor 16 inclined conveyor 41 Throttle check valve 17 Piston cylinder unit 42 Pressure accumulator 18 Swivel device 43 3 / 2-way valve 18a pendulum frame 44 Piston rod space 18b Tilting frame 45 piston chamber 19 framework structure 46 hydraulic circuit 20 framework structure 47 hydraulic line 20a carrying roller 48 Compensating line 20b axis 49 non-return valve 20c axis 50 Control device 20d circular track 51 sensor 20e circular track 52 sensor 21 Virtual pendulum axis 53 Belt cutting unit 22 Piston cylinder unit 54 middle section 22a Actuator / Swivel Cylinder 55 Page section 23 transverse axis 56 Frame joint 24 support wheel 57 Swivel axis 25 bracket 58 actuator 59 Knife bar 60 support arm 61 Frame 62 Trade fair wave 63 Potentiometer 64 Measuring shaft FR Forward direction KS console QR transverse direction VL Valve arrangement VR Valve arrangement

Claims

1. A self-propelled harvesting machine (1) with a height-adjustable pick-up device (6) on which a front attachment (3) which can be pivoted about a virtual pendulum axis (21) of the pick-up device (6) is disposed for picking up harvested material (7), wherein the pick-up device (6) is configured for the adaptive adjustment of a vertical distance of the front attachment (29) from the ground (30), wherein at least one support wheel (24) is respectively disposed at least on the outer lateral regions of the front attachment (3) and is respectively guided in a height-movable manner by a hydraulic cylinder (27) connected to a hydraulic circuit of a hydraulic system (33) which has a pressure source (34), wherein a regulation of the position of the front attachment (3) in the transverse direction (QR) during the harvesting operation for the transverse guidance of the front attachment (3) by pivoting about the virtual pendulum axis (21) is independent of at least one actuator (22a) which is controlled by the harvesting machine (1) and disposed on the pick-up device (6), characterized in that the regulation of the position of the front attachment (3) in the transverse direction (QR) is carried out by means of the support wheel (24) disposed on the respective lateral region, wherein the position regulation of the front attachment is configured to adjust a pressurization of the hydraulic cylinders (27) in alternation in order to compensate, in a pressure-regulated manner, for an actual transverse position of the front attachment (3) which deviates from a target transverse position.

2. The harvesting machine (1) according to claim 1, characterized in that the hydraulic cylinders (27) of the support wheels (24) are constructed as double acting hydraulic cylinders.

3. The harvesting machine (1) according to one of claims 1 to 2, characterized in that a control device (50) is provided which is configured to control a valve assembly (VL, VR) which is associated with the respective hydraulic cylinder (27), wherein the respective valve assembly (VL, VR) is configured to regulate a hydraulic pressure in the hydraulic cylinder (27) provided by the pressure source (34) as a function of a selected operational mode of the front attachment (3).

4. The harvesting machine (1) according to claim 3, characterized in that the control device (50) is disposed on the front attachment (3).

5. The harvesting machine (1) according to claim 3 or claim 4, characterized in that the control device (50) is configured for the autonomous control of the valve assemblies (VL, VR).

6. The harvesting machine (1) according to one of claims 1 to 5, characterized in that the front attachment (3) is associated with a plurality of mutually independently operating sensor devices (28) which are configured to detect the distance (29) between the front attachment (3) and the ground (30).

7. The harvesting machine (1) according to one of claims 1 to 6, characterized in that the respective support wheel (24) is associated with sensors (51, 52) which are configured to detect the position of the support wheel relative to the front attachment (3) and / or the pressure which is set in the respective hydraulic cylinder (27) of the support wheels (24).

8. The harvesting machine (1) according to one of claims 2 to 7, characterized in that the control device (50) is configured to evaluate signals from the sensor devices (28) in order to determine the actual transverse position, in order, by means of controlling the valve assemblies (VL, VR) in opposite directions during the pressurization of the hydraulic cylinders (27), to bring about a correction of the actual transverse position which deviates from the target transverse position of the front attachment (3) by loading or unloading the hydraulic cylinder (27) of the respective support wheel (24).

9. The harvesting machine (1) according to claim 8, characterized in that the control device (50) is configured to determine, with the aid of the evaluation of the signals from the sensor devices (28), the attainment of the target transverse position and to continue the control of the valve assemblies (VL, VR) in accordance with the selected operational mode.

10. The harvesting machine (1) according to one of claims 6 to 9, characterized in that the sensor devices (28) are constructed as sensor arms (31) or as contactlessly-operating distance sensors.

11. The harvesting machine (1) according to one of the preceding claims, characterized in that the front attachment (3) is constructed as a draper cutting unit (53) which comprises a central section (54) as well as at least two side sections (55) which are respectively pivotably connected by an articulated frame (56) to the central section (54) about a pivot axis (57) which extends parallel to the longitudinal axis of the harvesting machine (1), wherein, by means of an actuator (58), the respective side section (55) can be pivoted relative to the central section (54) about the pivot axis (57) transversely to the direction of travel (FR).

12. The harvesting machine (1) according to claim 11, characterized in that support arms (60) which can be pivoted about an axis which extends in the transverse direction (QR) are disposed on the central section (54) and the side sections (55) and support a cutter bar (59), wherein a plurality of sensor devices (28) are provided for the detection of a vertical deflection of the support arms (60) of the central section (54) and of the side sections (55), the sensor devices being constructed as a measuring shaft (62) which is non-rotatably fixed on the support arms (60) of the central section (54) and as at least one measuring shaft (64) which is non-rotatably fixed on the support arms (60) of the respective side section (55), and potentiometers (63) disposed thereon.