Chopping unit of a forage harvester and counter blade for a chopping unit

Abstract

Chopping unit (10) of a forage harvester, with a chopping drum (11) carrying chopping knives (15), with a counter-blade holder (17) carrying a counter-blade (16) for the chopping knives (15), wherein a top surface (20) of the counter-blade (16) facing away from the counter-blade holder (17) provides a cutting edge (21) of the counter-blade (16), characterized in that the top surface (20) of the counter-blade (16) is contoured such that the top surface (20) of the counter-blade (16) is inclined continuously towards the chopping drum (11) at least on one top surface section (26) facing the chopping drum (11) in the axial direction of the chopping drum (11) in the contact area with the chopping knives (15), wherein the top surface (20) of the counter-blade (16) is inclined at the chopping drum (11) the upper surface section (26) facing is contoured in such a way,that a first subsection (24) forming the cutting edge (21) runs parallel or approximately parallel to an underside (25) of the counter blade (16) facing the counter blade holder (17), and that a second subsection (23) adjoining this first subsection (24) is inclined towards the chopping drum (11).

Description

The invention relates to a chopping unit of a forage harvester and a counter blade for a chopping unit. From DE 196 52 656 B4, a chopping unit of a forage harvester is known, which has a chopping drum carrying several chopping knives. The chopping unit also has a counter blade for the chopping knives, which is mounted on a counter blade holder. The counter blade holder is also referred to as a saddle or anvil. A base element, designed as a base plate, runs below the chopping drum, the base element being detachably attached to the counter blade holder with a section facing the counter blade holder. The counter blade of the chopping unit according to DE 196 52 656 B4 comprises an upper surface facing away from the counter blade holder and a lower surface facing the counter blade holder, wherein the upper surface and the lower surface of the counter blade run continuously parallel to each other in the axial direction of the chopping drum and are inclined away from the chopping drum. From DE 196 51 694 A1, another chopping unit of a forage harvester with a counter blade is known. According to DE 196 51 694 A1, the counter blade has shaped profiles on its upper side facing the incoming crop and away from the counter blade holder, the boundaries of which form longitudinal cutting edges in some areas, extending in the direction of crop flow, with at least one transverse cutting edge arranged downstream of the longitudinal cutting edges. US 5 829 700 A discloses a counter blade for forage harvesters, consisting of a monolithic rod with a specially shaped horizontal bearing surface produced by milling and accommodating a series of tool mounting inserts and cutting tools made of sintered material, which can absorb shocks and wear of various kinds, wherein in the event of breakage a partial replacement of the cutting tools is possible by loosening screw connections with which the cutting tools are attached to the monolithic rod. All known counter-blades of chopping units are designed to optimize the cut in the area of ​​the chopping drum. This can reduce the chopping drum's ability to pick up the crop and increase the likelihood of blockages. There is a need for a chopping unit for a forage harvester that is characterized by a chopping drum that readily accepts the crop being processed and reduces the risk of clogging. A counter blade for such a chopping unit is also required. Based on this, the present invention aims to create a novel chopping unit for a forage harvester and a counter blade for a chopping unit. This problem is solved by a chopping unit of a forage harvester according to claim 1. According to the invention, the upper surface of the counter blade facing away from the counter blade holder is contoured such that the upper surface of the counter blade, at least on one upper surface section facing the chopping drum, is inclined continuously towards the chopping drum in the axial direction of the chopping drum in the contact area with the chopping knives. The angle of inclination of the upper section of the counter blade facing the chopping drum, which slopes continuously downwards in the axial direction of the chopping drum, increases the chopping drum's intake efficiency and reduces the susceptibility to clogging. The counter blade has no protrusions or similar features in the axial direction of the chopping drum, ensuring that the crop enters the chopping drum area without obstruction. According to the invention, the upper surface of the counter blade facing away from the counter blade holder is contoured on the upper surface section facing the chopping drum such that a first subsection forming the cutting edge runs parallel or approximately parallel to an underside of the counter blade facing the counter blade holder, and that a second subsection adjoining this first subsection is inclined towards the chopping drum. This not only ensures improved drum loading and a reduction in the likelihood of clogging, but also guarantees an optimal cutting angle for the crop to be chopped in the area of ​​the cutting edge designed as a transverse blade. Following further development, the upper surface of the counter blade facing away from the counter blade holder is inclined away from the chopping drum along a continuous section of the upper surface facing away from the chopping drum in the axial direction of the chopping drum. This makes it possible to rotate and reuse the counter blade when it is worn. The counter-edge according to the invention is defined in claim 6. Preferred embodiments of the invention are set forth in the dependent claims and the following description. Exemplary embodiments of the invention are explained in more detail with reference to the drawings, without being limited thereto. These show: Fig. 1 a schematic cross-section through a first chopping unit of a forage harvester according to the invention; Fig. 2 a schematic cross-section through a second chopping unit of a forage harvester according to the invention; Fig. 3 a detail of Fig. 2; Fig. 4 a schematic cross-section through a third chopping unit of a forage harvester according to the invention; Fig. 5 a detail of Fig. 4; Fig. 6 a schematic cross-section through a further chopping unit of a forage harvester according to the invention; Fig. 7 a detail of Fig. 6; Fig. 8 a schematic partial cross-section through a further chopping unit of a forage harvester according to the invention. The invention relates to a chopping unit of a forage harvester. Furthermore, the invention relates to a gene cutter for a chopping unit of a forage harvester. Fig. 1 shows a chopping drum 11 of a first chopping unit 10 according to the invention, wherein a pair of pre-compression rollers 12, 13 is positioned upstream of the chopping drum 11 of the chopping unit 10 in the material flow direction X. A so-called scraper 14 interacts with the lower pre-compression roller 12. The chopping drum 11 of the chopping unit 10 carries several chopping knives 15, two of which are shown in Fig. 1. A counter blade 16, mounted on a counter blade holder 17, interacts with the chopping knives 15. The counter blade holder 17 is preferably pivotable about a pivot axis 18 to allow the counter blade 16 to be angled more towards the chopping drum 11, particularly when the chopping knives 15 wear down. This allows the relative position of the counter blade 16 to the chopping drum 11, and thus to the chopping knives 15, to be adjusted. A bar 19 is arranged between the counter blade holder 17 and the counter blade 16. In the embodiment of a chopping unit 10 shown in Fig. 1, a top surface 20 of the counter blade 16 facing away from the counter blade holder 17 is contoured such that the top surface 20 of the counter blade 16, viewed in the axial direction of the chopping drum 11, is continuously inclined towards the chopping drum 11, starting from a cutting edge 21 of the counter blade 16 provided by the top surface 20 and extending towards an edge 22 of the top surface 20 of the counter blade 16 opposite the cutting edge 21. A virtual extension of the top 20 of the opposite side 16 intersects a straight line representing the material flow direction X at a virtual intersection point which, viewed in the material flow direction X, is positioned upstream of the chopping drum 11. According to the invention, in the embodiment shown in Fig. 1, the upper surface 20 of the counter blade 16, facing away from the counter blade holder 17, is inclined continuously towards the chopping drum 11 when viewed in the axial direction of the chopping drum 11. The upper surface 20 of the counter blade 16 therefore has no raised areas or the like. This increases the efficiency of the chopping drum 11 and reduces the risk of clogging in the area of ​​the pre-compression rollers 12, 13 and the intake housing. Harvested material enters the area of ​​the chopping drum 11 without blockages or similar issues. Fig. 2 and Fig. 3 show a section of a second shredding unit 10 according to the invention, wherein the embodiment of Fig. 2, Fig. 3 differs from the embodiment of Fig. 1 in that the upper surface 20 of the counter blade 16 facing away from the counter blade holder 17 is subdivided into two sections 23, 24. The upper surface 20 of the counter blade 16, facing away from the counter blade holder 17, is contoured such that the section 24 of the upper surface 20 of the counter blade 16 forming the cutting edge 21 serving as a transverse cutting edge runs parallel or approximately parallel to a lower surface 25 of the counter blade 16 facing the counter blade holder 17 and is therefore not inclined towards the chopping drum 11, whereas the section 23 of the upper surface 20 of the counter blade 16 adjoining this section 24 is inclined towards the chopping drum 11, as described with reference to Fig. 1, such that a virtual extension of the section 23 of the upper surface 20 of the counter blade 16 intersects the axis of the material flow direction X at a virtual intersection point, which, viewed in the material flow direction X, is positioned in front of the chopping drum 11. The design of Fig. 2 and Fig. 3, as well as the design of Fig. 1, increases the ease of intake of the chopping drum 11 for the harvested material and reduces the susceptibility to clogging; furthermore, an optimal cutting angle for the harvested material is provided in the area of ​​the cutting edge 21 serving as a cross-cutting edge. The sections 23 and 24 of the upper surface 20 of the counter blade 16 are, viewed in the axial direction of the chopping drum 11, at least in the contact area with the chopping knives, each uniformly contoured throughout, so that no protrusions or the like are formed in the area of ​​either section 23, 24. A further embodiment of a chopping unit 10 according to the invention is shown in Figs. 4 and 5. In the embodiment of Figs. 4 and 5, the upper surface 20 of the counter blade 16, facing away from the counter blade holder 17, is subdivided into two upper surface sections 26, 27, wherein the upper surface section 26, which forms the cutting edge 21 and faces the chopping drum 11, is inclined towards the chopping drum 11, whereas the upper surface section 27 of the upper surface 20 of the counter blade 16, which forms the edge 22 of the upper surface 20 opposite the cutting edge 21 and faces away from the chopping drum 11, is inclined away from the chopping drum 11, wherein these two upper surface sections 26, 27 intersect in a cutting line 28, forming a roof-shaped contour of the upper surface 20 of the counter blade 16. The area where the two upper surface sections 26, 27 meet may also be somewhat flattened. The cutting line 28 of the two upper surface sections 26, 27 runs in the axial direction of the chopping drum 11, wherein the two upper surface sections 26, 27 are preferably symmetrical with respect to this cutting line 28, so that by simply rotating the counter blade 16 after wear of the cutting edge 21 the opposite edge 22 can be used as a new cutting edge. Another embodiment of the invention is shown in Figs. 6 and 7. The embodiment of Figs. 6 and 7 combines the features of the embodiments of Figs. 2, 3 and 5, 6. In the embodiment shown in Figs. 6 and 7, both differently inclined upper surface sections 26, 27 of the upper surface 20 of the counter blade 16 are subdivided into the two subsections 23, 24, wherein the subsections 24 of the upper surface sections 26, 27 again run parallel to a lower surface 25 of the counter blade, while the subsections 23 are inclined, namely the subsection 26 of the upper surface section 26 is inclined towards the chopping drum 11 and the subsection 26 of the upper surface section 27 is inclined away from the chopping drum 11, again forming a roof-shaped contour of the upper surface 20 of the counter blade 16, the section line 28 of which runs in the axial direction of the chopping drum 11. The contouring of the counter blade 16 according to the invention in the area of ​​its upper surface 20 facing away from the counter blade holder 17 increases the ease with which the chopping drum 11 can accommodate the crop to be chopped. This reduces the likelihood of clogging in the area of ​​the pre-compression rollers 12, 13 or a feed housing. The symmetrical design of the embodiments of Fig. 4, Fig. 5 and Fig. 6, Fig. 7 is preferred, since the counter-cutting edge 16 can be reused after wear by turning it. The embodiment shown in Fig. 6 and Fig. 7 is particularly preferred, as it not only increases ease of handling but also ensures an optimal cutting angle in the area of ​​the cutting edge 21. Another embodiment of a chopping unit 10 according to the invention is shown in Fig. 8. In the embodiment of Fig. 8, the upper surface 20 of the counter blade 16, facing away from the counter blade holder 17, is divided into two upper surface sections 29, 30, wherein the upper surface section 29, which forms the cutting edge 21 and faces the chopping drum 11, is inclined towards the chopping drum 11, whereas the upper surface section 30 of the upper surface 20 of the counter blade 16, which forms the cutting edge 22 of the upper surface 20 opposite the cutting edge 21 and faces away from the chopping drum 11, runs parallel or approximately parallel to the lower surface 25 of the counter blade 16. According to the embodiments shown in Fig. 2 or Fig. 3, the upper surface section 29 facing the chopping drum 11 can additionally be subdivided into two sections, as indicated by the dashed line 31. The section forming the cutting edge 21, which serves as a transverse cutting edge, runs parallel or approximately parallel to the underside 25 of the counter blade 16 and forms a more favorable cutting angle together with the chopping knives 15. The other section is inclined in the material flow direction X towards the chopping drum 11 and improves the acceptance of material by the chopping drum 11. A correspondingly designed counter blade 16 can be used in the illustrated installation position with respect to the crop flow direction X for problematic harvesting conditions. For more favorable harvesting conditions, a counter blade 16 contoured according to Fig. 8 can advantageously be simply reversed so that the upper surface section 30 with the cutting edge 22 interacts with the chopping drum 11. With the chopping units and counter-blades described above according to the invention, the harvesting result can be improved, especially under problematic harvesting conditions, such as wet, sticky grass. Reference symbol list 10 Chopping unit 11 Chopping drum 12 Pre-compression roller 13 Pre-compression roller 14 Scraper 15 Chopping knife 16 Counter blade 17 Counter blade holder 18 Axle 19 Bar 20 Top side 21 Cutting edge 22 Edge 23 Section 24 Section 25 Bottom side 26 Top side section 27 Top side section 28 Cutting line 29 Top side section 30 Top side section 31 Dashed line

Claims

Chopping unit (10) of a forage harvester, with a chopping drum (11) carrying chopping knives (15), with a counter-blade holder (17) carrying a counter-blade (16) for the chopping knives (15), wherein a top surface (20) of the counter-blade (16) facing away from the counter-blade holder (17) provides a cutting edge (21) of the counter-blade (16), characterized in that the top surface (20) of the counter-blade (16) is contoured such that the top surface (20) of the counter-blade (16) is inclined continuously towards the chopping drum (11) at least on one top surface section (26) facing the chopping drum (11) in the axial direction of the chopping drum (11) in the contact area with the chopping knives (15), wherein the top surface (20) of the counter-blade (16) is inclined at the chopping drum (11) the upper surface section (26) facing is contoured in such a way,that a first section (24) forming the cutting edge (21) runs parallel or approximately parallel to an underside (25) of the counter blade (16) facing the counter blade holder (17), and that a second section (23) adjoining this first section (24) is inclined towards the chopping drum (11). Chopping unit according to claim 1, characterized in that the upper surface (20) of the counter blade (16) is inclined continuously away from the chopping drum (11) in the axial direction of the chopping drum (11) at an upper surface section (27) facing away from the chopping drum (11). Chopping unit according to claim 2, characterized in that the upper section (27) of the counter blade (16) inclined away from the chopping drum (11) and the upper section (26) of the counter blade (16) inclined towards the chopping drum (11) intersect, forming a roof-shaped contour of the upper surface (20) of the counter blade (16). Chopping unit according to claim 2 or 3, characterized in that the upper surface (20) of the counter blade (16) is symmetrical with respect to a cutting line (28) of the upper surface sections (26, 27). Chopping unit according to one of claims 2 to 4, characterized in that the upper surface (20) of the counter blade (16) is contoured on the upper surface section (27) facing away from the chopping drum (11) such that a first subsection (24) runs parallel or approximately parallel to the underside (25) of the counter blade (16) facing the counter blade holder (17), and that a second subsection (23) adjoining this first subsection (24) is inclined away from the chopping drum (11). Counter blade (16) for a chopping unit (10) of a forage harvester, which can be mounted on a counter blade holder (17) of the chopping unit (10), wherein a top surface (20) provides a cutting edge (21), characterized in that the top surface (20) is inclined continuously towards the chopping drum (11) at least on one top surface section (26) facing the chopping drum (11), wherein the top surface (20) is contoured on the top surface section (26) facing the chopping drum (11) such that a first subsection (24) forming the cutting edge (21) runs parallel or approximately parallel to a bottom surface (25), and that a second subsection (23) adjoining this first subsection (24) is inclined towards the chopping drum (11). Counter blade according to claim 6, characterized in that the upper surface (20) is inclined continuously away from the chopping drum (11) at an upper surface section (27) facing away from the chopping drum (11). Counter blade according to claim 7, characterized in that the upper surface section (27) inclined away from the chopping drum (11) and the upper surface section (26) inclined towards the chopping drum (11) intersect, forming a roof-shaped contour of the upper surface (20). Counter-edge according to claim 7 or 8, characterized in that the top surface (20) is symmetrical with respect to a section line (28) of the top surface sections (26, 27). Counter blade according to claim 6, characterized in that the top surface (20) of the counter blade (16) is divided into two top surface sections (29, 30), wherein one top surface section (29), which forms a cutting edge (21), is inclined towards the chopping drum (11), and the other top surface section (30) of the top surface (20), which is a cutting edge (22) opposite the cutting edge (21), runs parallel or approximately parallel to the bottom surface (25) of the counter blade (16). Counter blade according to one of claims 7 to 10, characterized in that the upper surface (20) is contoured on the upper surface section (27) facing away from the chopping drum (11) such that a first subsection (24) runs parallel to the underside (25), and that a second subsection (23) adjoining this first subsection (24) is inclined away from the chopping drum (11).

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