FIELD HACKERS

Description

[0001] The present invention relates to a forage harvester.

[0002] A forage harvester typically has a chassis with frame members extending longitudinally of the forage harvester and interconnected by transverse beams, to which a front axle, rear wheels, an engine, a chopper, etc., are mounted. Such a forage harvester is disclosed in US2006185337.

[0003] The main component of the chopper is a chopper drum fitted with knives. A stream of crop is fed toward the chopper drum while the drum rotates, cutting the crop into pieces. To ensure consistent rotation despite the varying resistance of the crop, the chopper drum must have a high moment of inertia and a correspondingly large diameter and high mass. This, along with the widely fluctuating cutting forces on the knives during operation, necessitates a powerful shaft and correspondingly large, heavy-duty bearings. Bearing play that allows the chopper drum to shake impairs cutting quality and also leads to increased bearing wear, which in turn increases the bearing play.

[0004] One object of the invention is to create a forage harvester which enables low-wear bearings and precise guidance of the movement of the chopper drum over a long period of time.

[0005] The problem is solved by a field chopper with a chopper drum assembly and two frame parts, between which the chopper drum assembly is rotatably suspended, with the chopper drum assembly being held on both frame parts by a clamping bearing each defining a rotation axis, the contact points between a frame part-side element and an assembly-side element of the clamping bearing lie on a spherical surface centered on the rotation axis. With this design, not each clamping bearing individually defines the rotation axis, but rather each clamping bearing defines only a single point, the center of the spherical surface, as the point through which the rotation axis must pass. This allows the chopper drum assembly to be mounted on the frame parts free of internal stress and to rotate relative to them with little friction and wear.

[0006] To ensure permanently secure clamping, both elements of the clamping bearing should have spherical surfaces that, as they are shaped complementarily to each other, touch each other over a large area.

[0007] The assembly-side element of the clamping bearing uts is typically a ring through which a shaft of the chopper drum assembly extends, and in which the spherical surface is an outer peripheral surface.

[0008] To enable removal of the chopper drum assembly, the frame part-side element comprises two parts into which the spherical surface of the frame part-side element is distributed.

[0009] In particular, a lower of the two parts should be an integral part of one of the frame parts in order to be able to stably support the chopper drum assembly even when the upper of the two parts is detached.

[0010] A clamping screw is sufficient to pull the two parts together and clamp the assembly-side element. If this clamps the parts together on one side of the shaft, a joint connection can be provided between the parts on the opposite side.

[0011] According to a preferred embodiment, the chopper drum assembly comprises a shaft rotatably mounted in the clamping bearings and an adapter for a harvesting header connected to the shaft in a rotationally fixed manner. By rotating the shaft and, with it, the adapter, the height above the ground of the harvesting header can be adjusted.

[0012] The chopping drum is preferably mounted on the shaft for rotation. Since the shaft only has to make small, slow rotations, it can be mounted on a plain bearing in the clamping bearing.

[0013] To drive the rotation of the shaft (and thus the height adjustment of the adapter), a hydraulic actuator can be provided between the frame parts and the chopper drum assembly.

[0014] Further features and advantages of the invention will become apparent from the following description of exemplary embodiments with reference to the accompanying figures. They show: Fig. 1 is a schematic representation of a forage harvester; Fig. 2 is a view of a frame of the forage harvester and a chopper drum assembly mounted in the frame; Fig. 3 is a closed clamping bearing; Fig. 4 is parts of the clamping bearing; Fig. 5 is an axial section through the clamping bearing; and Fig. 6 is an oblique view of the frame and a housing of the chopper drum assembly from below.

[0015] Fig. 1shows a schematic representation of a forage harvester 1. The body of the forage harvester 1 is shown cut open at its front, below a driver's cab 2, to show the forage harvester's internal crop-processing components. One of these components is a chopper drum assembly with a chopper drum 4 rotating around an axis 3 extending in the transverse direction of the vehicle.

[0016] A conveyor device 5 for crop material is arranged in front of the chopper drum assembly. The conveyor device 5 comprises several pairs of rollers 6, 7, each of which defines a gap and is driven in opposite directions to feed the crop material passing through the gap to the chopper drum 4.

[0017] The conveyor device 5 in turn carries a harvesting attachment 6 which can be exchanged to suit the plant material to be harvested.

[0018] Crop shredded in the chopper drum assembly is fed to a post-accelerator 9, which gives the shredded crop the necessary speed to pass through a discharge spout 10 and be transferred to an accompanying vehicle (not shown).

[0019] Fig. 2 and 3 shows a front part of a frame 11 of the forage harvester 1 and the chopper drum assembly 12 mounted therein in a perspective view obliquely from the front. The frame 11 comprises two frame parts 13 extending essentially horizontally in the longitudinal direction of the vehicle, e.g., in the form of T- or double-T profiles, which are rigidly connected to one another by cross members (not visible in the figure) and on which a front axle and steerable rear wheels of the forage harvester 1 are suspended.

[0020] The front end of the frame parts 13 is in Fig. 2hidden behind a pulley 14 driving the rotation of the chopper drum or a housing 15 surrounding the chopper drum.

[0021] Fig. 3 shows this front end in a detailed view. The frame part 13 terminates in a clamping bearing 16, which is provided to receive a shaft of the chopper drum assembly 12. Only an annular element 17 of the chopper drum assembly 12 is shown, which is provided to receive a shaft that—as will be described in more detail below—connects the pulley 14 to the housing 15 and the chopper drum 4.

[0022] A frame part-side element 18 of the clamping bearing 16 comprises a part 19 in the form of a ring sector, which is firmly connected to the frame part 13 and whose concavity 20 (see also Fig. 4) is directed upwards so that the chopper drum assembly 12 can be stably supported during installation in or removal from the forage harvester 1 by inserting the annular element 17 into the concavity 20.

[0023] A second ring-sector-shaped part 21 of the frame-side element 18 is connected to the frame part 13 via a joint 22. The front tips of the parts 19, 21 each have a bore in which a clamping screw 23 can be mounted. To insert the chopper drum assembly 12 into or remove it from the concavity 20, the clamping screw 23 is removed and the part 21 is folded up.

[0024] As in Fig. 4As can be seen, the concavity 20 is part of a spherical surface, just like the outer peripheral surface 24 of the annular element 17. Therefore, when inserted into the concavity 20, the annular element 17 can pivot about two axes orthogonal to the shaft. When the chopper drum assembly 12 is inserted into the two parts 19, the orientation of its axis can freely adapt to any tolerances in the positioning and alignment of the parts 19, so that when the clamping screw 23 is tightened and the annular element 17 is clamped between the parts 19, 21, no internal stresses result in the chopper drum assembly 12.

[0025] The spherical surfaces of the concavity 20 and the outer peripheral surface 24 each have the same radii; moreover, the part 21 can have a concavity with the same radius, so that the parts 19, 21 rest against the outer peripheral surface 24 over a large area when tightened.

[0026] Fig. 5shows an axial section of one of the clamping bearings 16 and the shaft 25 of the chopper drum assembly 12 received therein. The center of the spherical surfaces of the concavity 20 and the outer peripheral surface 24 lie on the axis 3 of the shaft 25. The shaft 25 comprises a hollow shaft 26 and an inner shaft 27 running concentrically inside it. The inner shaft 27 carries the pulley 14 on one side of the clamping bearing 16 and the chopper drum 4 on the other. The hollow shaft 26 carries the housing 15. A rolling bearing 28 between the two ensures the rotatability of the hollow shaft 26 and the inner shaft 27 relative to one another, so that the pulley 14 can drive the rotation of the chopper drum 4 while the housing 15 remains at rest.A plain bearing 29 between the hollow shaft 26 and the annular element 17, in the simplest case a lubrication between the outer surface of the hollow shaft 26 and the inner surface of the annular element 17, enables rotation of the hollow shaft 26 and the housing 15 about the axis 3 independently of the rotation of the chopping drum 4.

[0027] Fig. 6shows a view of the frame of the forage harvester 1 and the housing 15 of the chopper drum assembly 12, obliquely from below. A square adapter 30 on the front of the housing 15 is provided for mounting the harvesting header 8 (not shown in this figure) or for coupling a lifting machine to it to assist in the installation and removal of the chopper drum assembly 12 from the forage harvester 1. A hydraulic actuator 31 extends below each of the frame parts 13 in the longitudinal direction of the vehicle. A rear end of each actuator 31 is connected to the frame, and the front ends jointly engage a crossbeam 32 of the housing. By extending together, the actuators 31 pivot the housing 15 about the axis 3 and thereby, if necessary, lift the harvesting header 8 mounted on the adapter 30.Due to the pivoting mobility of the annular elements 17 in the frame-side elements 18, their inner sides are precisely aligned with each other, allowing the hollow shaft 26 to rotate within them without experiencing bending stress. This ensures smooth, low-wear rotation not only of the plain bearing 29, but also of the roller bearing 28. Reference symbol

[0028] 1Forage harvester 2Driver's cab 3Axle 4Chopper drum 5Conveyor system 6Pair of rollers 7Pair of rollers 8Harvesting head 9Post-accelerator 10Discharge spout 11Frame 12Chopper drum assembly 13Frame part 14Pulley 15Housing 16Clamping bearing 17(Annular) element 18(Frame part-side) element 19Part of 18 20Concavity 21Part of 18 22Joint 23Clamping screw 24Outer peripheral surface 25Shaft 26Hollow shaft 27Inner shaft 28Rolling bearing 29Plain bearing 30Adapter 31Actuator 32Crossbeam

Claims

1. A forage harvester with a chopping drum assembly (12) and two frame parts (13), between which the chopping drum assembly (12) is rotatably suspended, wherein the chopping drum assembly (12) is retained on both frame parts (13) by a respective clamp bearing (16) defining an axis of rotation (3), characterized in that contact points between an element (18) on the frame part side and an element (17) on the assembly side of the clamp bearing (16) lie on a spherical surface centred on the axis of rotation (3), wherein the element (18) on the frame part side comprises two parts (19, 21) and the spherical surface (20) is divided over both parts (19, 21), wherein at least one tensioning screw (23) is provided in order to draw the two parts (19, 21) together.

2. The forage harvester according to claim 1, characterized in that the contact points lie on mutually complementary spherical surfaces (20, 24) of the elements (17, 18).

3. The forage harvester according to claim 1 or claim 2, characterized in that the element (17) on the assembly side is a ring through which a shaft (25) of the chopping drum assembly (12) extends, and in that the spherical surface is an outer circumferential surface (24) of the ring.

4. The forage harvester according to one of the preceding claims, characterized in that the chopping drum assembly (12) comprises a shaft (26) which is rotatably received in the clamp bearings (16) and an adapter (30) for a front harvester attachment (6) which is connected to the shaft (26) in a manner which is fixed against rotation.

5. The forage harvester according to claim 4, characterized in that the chopping drum assembly (12) comprises a chopping drum (4) which is rotatably mounted on the shaft (26).

6. The forage harvester according to claim 4 or claim 5, characterized by at least one hydraulic actuator (31) for actuating a pivoting movement of the adapter (30) about the axis of rotation (3).