Harvesting Head Comprised of Several Sections with Bend Protection and Method for Height Control of the Harvesting Head

Abstract

A harvesting head has a middle section connected to a carrier device and at least one side section connected by an articulated connection to the middle section about which the side section pivots between a lower and an upper limit value. The carrier device has a height adjustment device whose adjusting movements are controlled by a control. The harvesting head has a sensor transmitting a sensor signal to the evaluation device at least upon pivoting of the side section when a limit value has been achieved during pivoting of the side section to the middle section. The evaluation device switches upon the presence of a corresponding sensor signal into a correction mode for height adjustment of the carrier device. The evaluation device outputs an adjusting signal in the correction mode to adjust the carrier device up or down by the evaluation device according to the sensor signal.

Claims

1. A harvesting head (2) comprised of several sections (4, 6) for being attached to a harvester, with a middle section (4) comprising the connection elements (8) with which the middle section (4) can be attached to a carrier device of the harvester, and with at least one side section (6) which is connected by an articulated connection (12) to the middle section (4) and about which the side section (6) can pivot between a lower and an upper limit value, wherein the carrier device comprises a device for the height adjustment whose adjusting movements are controlled by an evaluation device (16) which is connected to sensors (10) which constantly measure the ground distance (30) of one or more sections (4, 6) of the harvesting head (2) during the forward travel of the harvester, the evaluation device (16) converts the sensor signals of the sensors (10) into adjusting commands for changing the height level of the device for adjusting the height and transfers these adjusting commands to an actuator of the device for the height adjustment, wherein the harvesting head (2) comprises a sensor (14) which transmits a sensor signal via a communication means to the evaluation means (16) upon a pivoting movement of the side section (6) at least when a limit value has been achieved during the pivoting motion of the side section (6) to the middle section (4), the evaluation device (16) comprises an evaluation circuit which switches the evaluation device (16) upon the presence of an appropriate sensor signal into a correction mode for the height adjustment of the carrier device, and the evaluation device (16) outputs an adjusting signal in the correction mode with which the carrier device is adjusted up or down by the evaluation device (16) according to the sensor signal, and the evaluation device (16) emits an adjusting signal in the correction mode with which the carrier device is adjusted by the evaluation device (16) into a movement which rotates the harvesting head (2) about the longitudinal middle axis (24).

2. The harvesting head (2) according to claim 1, wherein the evaluation device (16) queries the sensor values of the sensors continuously measuring the distance to the ground (30) of the harvesting head (2) in the correction mode, determines whether a minimum distance to the ground (26) is being maintained, and blocks a further lowering of the carrier device by a safety circuit if the query of the sensor values signals the achieving of the minimum distance.

3. The harvesting head (2) according to claim 1, wherein the evaluation device (16) queries the sensor values of the sensors (10) continuously measuring the distance to the ground (30) of the harvesting head (2), compares the series of this sensor data and its sequence and derives from it a trend prediction of an adjusting direction imminent from the measuring of the distance to the ground (30) for the middle section (4), queries the sensor values of the sensors continuously monitoring the pivoting motion of the side section (6), compares the series of the sensor data in its sequence and derives from it a trend prediction of an adjusting direction imminent from the measuring of the pivoting movements of the side sections (6) for the middle section (4), conducts both trend predictions to a bandwidth filter and emits an adjusting signal in the case of an absence of a value from the bandwidth filter with which signal the carrier device is moved up or down by the evaluation device (16) according to the results of the evaluation of the bandwidth filter.

4. The harvesting head (2) according to claim 1, wherein the support wheels (34) arranged on the side sections (6) can be adjusted in height, the adjustment in height of the support wheels (34) takes place by the evaluation device (16), and the evaluation device (16) holds the support wheel (34) in the correction mode of the associated side section (6) in the current position or moves it downward if a sensor (14) for the particular side section (6) transmits a sensor signal to the evaluation device (16) which indicates that the side section (6) is located in the area of its lower stop and/or of the lower limit value.

5. A method for regulating the height of a harvesting head (2) according to claim 1, wherein the harvesting head (2) comprises an evaluation device (16) with which a sensor (14) is queried with software support which upon a pivoting movement of the side section (6) transmits at least then a sensor signal via a communication means to the evaluation device (16) if a limit value has been reached during the pivoting movement of the side section (6) to the middle section (4), the evaluation device (16) switches upon the presence of a corresponding sensor signal via an evaluation circuit into a correction mode for the height adjustment of the carrier device, and the evaluation device (16) outputs an adjusting signal in the correction mode with which the carrier device is adjusted up or down by the evaluation device (16) according to the sensor signal, and the evaluation device (16) outputs an adjusting signal in the correction mode with which the carrier device is adjusted by the evaluation device (16) into a movement which rotates the harvesting head (2) about the longitudinal middle axis (24).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The invention will now be explained in detail using a preferred exemplary embodiment and referring to the attached drawings.

[0025] In the drawings:

[0026] FIG. 1: shows a oblique rear view of a harvesting head,

[0027] FIG. 2: shows a view onto the harvesting head resting on a flat ground,

[0028] FIG. 3: shows a view onto the harvesting head traveling through a trough, and

[0029] FIG. 4: shows a view onto a harvesting head traveling over a crest.

DESCRIPTION OF PREFERRED EMBODIMENTS

[0030] FIG. 1 shows a view of a harvesting head 2 from an oblique rear perspective. The harvesting head 2 consists in the exemplary embodiment of a middle section 4 and two side sections 6 attached to it. The harvesting head 2 is connected by connection elements 8 to the entrance conduit of a combine.

[0031] The harvesting head 2 comprises in the exemplary embodiment a total of four sensors 10 with which the distance to the ground of the harvesting head 2 can be continuously measured. The sensors 10 are in the exemplary embodiment pivotable ground surface feelers which are coupled to a rotary potentiometer.

[0032] The middle section 4 is connected to each of the side sections 6 by an articulated connection 12. The articulated connection 12 consists of a rotary shaft about which the side sections 6 can pivot with their free ends up or down.

[0033] Sensors 14 are connected to the two articulated connections 12 with which sensors the bending angle which a side section 6 has to the middle section 4 in a particular state of use can be determined.

[0034] The harvesting head 2 comprises an evaluation device 16 which is connected by connection lines 18 to the sensors 10 and by connection lines 20 to the sensors 14. The particular sensor values of the sensors 10, 14 can be transmitted by the connection lines 18, 20 to the evaluation device 16.

[0035] In the evaluation device 16 a computer converts the sensor signals of the sensors 10 into adjusting commands for changing the height level of the device for the height adjustment with an appropriately designed software. These adjusting commands are forwarded by a connection line 22 to the device for the height adjustment which is located in the combine not shown in detail in FIG. 1. Therefore, the connection line 22 designates an interface to the electronic system and actuating system of the harvester to which the harvesting head 2 is attached.

[0036] The device for height adjustment cannot only raise and lower the harvesting head 2 in accordance with its design but it is also additionally possible to rotate the harvesting head 2 about the longitudinal middle axis 24 if this seems to be necessary based on the sensor data of the sensors 10 and/or of the sensors 14.

[0037] The undercarriage of the harvesting head 2 consists of the two support wheels 34 associated with one of the side sections. The support wheels 34 can be adjusted in height in the exemplary embodiment.

[0038] FIG. 2 shows the harvesting head 2 in a front view in a harvesting situation in which the harvesting head 2 is being moved over a flat ground 26. No bending angle arises between the middle section 4 and the side sections 6 due to the flat ground 26.

[0039] FIG. 3 shows a possible harvesting situation in which the harvesting head 2 travels through a trough 28. While the middle section 4 is in an almost horizontal position, the two side sections 6 with their free ends are pivoted upward so that a bending angle of circa 10 is adjusted between the middle section 4 and the two side sections 6. While the ground distance 30 in the area of the middle section 4 is so great that the surface 2 could still be lowered at this degree of distance, the ground distance 30 is so slight in the area of the free ends of the side sections 6 that upon a further lowering of the middle section 4 downward, the structural components of the articulated connection 12 would be exposed to a significant stress. Upon a further lowering of the middle section 4 the outer ends of the side sections 6 would violently drag on the ground 26, which could lead to damage to the surface 2 and to the carrier device on the combine. In this situation the correction mode in the evaluation device 16 should prevent that the middle section 4 is lowered down even more. If the sensors 14 report the reaching of a limit value in this position of use of the harvesting head, it is all the more important that the evaluation device 16 switches into the correction mode and outputs an adjusting signal to the carrier device in this correction mode upon which signal the harvesting head 2 is raised upward in a direction to remove the stress from the articulated connections 12 between the side sections 6 and the middle section 4.

[0040] FIG. 4 shows the harvesting head 2 when traveling over a crest 32. This view does not show the support wheels 34. It can be recognized in this view that the ground distance 30 is very large in the area of the free ends of the side sections 6 whereas it is reduced to a minimum distance in the area of the middle section 4 in the middle area. In this harvesting situation the outer sensors 10 would report to the evaluation device 16 that a further raising of the support wheels 34 of the undercarriage is necessary in order to reestablish a contact with the ground of the particular side section 6 even though the side sections 6 already freely hover over the ground in a mechanically limited manner. However, the evaluation device 16 already has reports from the bending angle sensors 14 in this harvesting situation according to which a limit value has been exceeded in the bending angles of the side sections 6. In this harvesting situation the evaluation device 16 would also tend, on account of the sensor data of the outer sensors 10, to further raise the support wheels 34. However, it can be ensured here by a safety circuit that the side support wheels 34 are not raised further but remain in their position or are even moved downward. As a consequence, they are in a position after the end of this harvesting situation which makes possible the new assuming of the height guidance for the particular side section 6 without a distinct adaptation of the height position of the support wheels 34.

[0041] The invention is not limited to the above exemplary embodiment. A person skilled in the art will have no difficulty in modifying the exemplary embodiment in a manner that seems appropriate to him in order to adapt it to a concrete application.