MOWER KNIFE DEVICE

Abstract

The invention relates to a mower knife device (100) with (i) a double-knife cutting system (111), wherein the double-knife cutting system (111) comprises an upper cutting knife (140) and a lower cutting knife (180), which are configured to be movable in translation relatively to one another, wherein the upper cutting knife (140) and the lower cutting knife (180) each comprise a plurality of blade elements (145) and a knife back (144, 184), wherein the blade elements (145) are connected to each other via the knife back (144, 183) and are arranged substantially in a knife plane (150), and (ii) a knife bar (110) which comprises a first extension (112) in the direction of an axis (170) orthogonal to the knife plane (150) and which is configured to hold the double-knife cutting system (111), wherein a gap (160) is arranged between the knife bar (110) and the double-knife cutting system (111), wherein a section of the knife back (144, 184) adjoins the gap (160), wherein the section of the knife back (144, 184) adjoining the gap (160) is bent in the direction of the orthogonal axis (170).

Claims

1-12. (canceled)

13. A mower knife device, comprising: a double-knife cutting system, wherein the double-knife cutting system comprises an upper cutting knife and a lower cutting knife, which are configured to be movable in translation relatively to one another, wherein the upper cutting knife and the lower cutting knife each comprise a plurality of blade elements and a knife back, wherein the blade elements are configured to be connected to one another via the knife back and arranged essentially in a knife plane, a knife bar which comprises a first extension in the direction of an axis orthogonal to the knife plane and which is configured to hold the double-knife cutting system, wherein a gap is arranged between the knife bar and the double-knife cutting system, wherein a section of the knife back adjoins the gap, wherein the section of the knife back adjacent to the gap is bent in the direction of the orthogonal axis.

14. The mower knife device according to claim 13, wherein the knife bar is arranged at the level of the double-knife cutting system, in particular symmetrically around the knife plane, and/or wherein the section of the knife back of the upper cutting knife adjacent to the gap and the section of the knife back of the lower cutting knife adjacent to the gap are bent substantially symmetrically with respect to the knife plane.

15. The mower knife device according to claim 13, wherein the section of the knife back adjacent to the gap is bent along an entire width of the double-knife cutting system, in particular uniformly.

16. The mower knife device according to claim 13, wherein the section of the knife back adjacent to the gap is bent such that a distance between a projecting part of the bent knife back of the upper cutting knife and a projecting part of the bent knife back of the lower cutting knife in the direction of the orthogonal axis corresponds to at least the first extension of the knife bar.

17. The mower knife device according to claim 13, wherein the bent section of the knife back is flat and comprises a bending angle of between 5? and 45?, preferably 15?, relative to the knife plane.

18. The mower knife device according to claim 13, wherein each blade element comprises two strictly convexly formed boundaries with cutting edges arranged thereon, wherein the cutting edge of one blade element and the opposite cutting edge of an adjacent blade element extend continuously over the knife back.

19. The mower knife device according to claim 18, wherein each blade element is symmetrically constructed around a centerline which runs parallel to a direction from a blade tip of the blade element to the knife bar, wherein the two strictly convexly formed boundaries in the region of the blade tip run substantially parallel to the centerline.

20. The mower knife device according to claim 18, wherein the cutting edges are flat.

21. The mower knife device according to claim 13, comprising a knife head to initiate a drive movement of a lateral drive on the double-knife cutting system, wherein the knife head is fixedly connected directly to the upper cutting knife at a remaining section, which comprises sections of the knife back located outside the bent section of the knife back, and in particular is fixedly connected without additional reinforcement.

22. The mower knife device according to claim 13, wherein the knife back comprises an extension of at least 10 mm, preferably 33 mm, in the direction from a blade tip of the blade element to the knife bar, wherein the bent section of the knife back comprises an extension of at least 5 mm, preferably half of the extension of the knife back, in the direction from a blade tip of the blade element to the knife bar.

23. The mower knife device according to claim 13, wherein the upper cutting knife and/or the lower cutting knife is formed in one piece, in particular made of a flat steel and subsequently bent.

24. The mower knife device according to claim 13, wherein the remaining sections of the upper cutting knife and of the lower cutting knife are formed substantially flat outside the bent sections of the knife back.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The drawings used to illustrate the embodiment example show:

[0033] FIG. 1 a schematic view of a double-knife cutting system according to the invention,

[0034] FIG. 2a schematic sectional view of a mower knife device according to the invention, and

[0035] FIG. 3 a perspective view of a mower knife device according to the invention.

[0036] In principle, identical parts are marked with identical reference signs in the figures.

WAYS TO CARRY OUT THE INVENTION

[0037] FIG. 1 shows a schematic top view of a double-knife cutting system 111 according to the invention. The double-knife cutting system 111 comprises an upper cutting knife 140 and a lower cutting knife 180, which are configured to be movable in translation relatively to one another. The upper cutting knife 140 and the lower cutting knife 180 each comprise a plurality of blade elements 145, each of which comprises two strictly convex boundaries 148 with cutting edges 147 arranged thereon. The blade elements 145 are each configured symmetrically around a centerline 149, wherein the boundaries 148 near the blade tip 142 or the centerline 149 run approximately parallel to the centerline 149 and form a larger angle to the centerline 149 in an area between two adjacent blade elements 145. The blade elements 145 of the upper cutting knife 140 are interconnected by a knife back 144, and the blade elements 145 of the lower cutting knife 180 are also interconnected by a knife back 184, wherein the knife back 144, 184 extends between a first knife back boundary line 146 and an end surface 143.

[0038] The knife back 144, 184 is bent in a section adjacent to a gap 160 between the double-knife cutting system 111 and a knife bar 110 (shown in FIG. 2 and FIG. 3). The two lower lines shown in

[0039] FIG. 1 show a top view of end surfaces 143 of the bent knife back 144, 184, and the line 141 drawn above them schematically shows the beginning of the bent sections of the knife backs 144, 184 of the upper 140 and the lower 180 cutting knife, wherein the latter line 141 may, for example, represent a bending edge at which the knife back 144, 184 is bent. The section of the knife back 144, 184 adjacent to the gap 160 may also be bent by rolling, although other types of bending and forming are also possible.

[0040] FIG. 2 shows a schematic sectional view of a mower knife device 100 according to the invention comprising a double-knife cutting system 111 and a knife bar 110, wherein the knife bar 110 is connected to the double-knife cutting system 111 by means of holding devices (not shown). The double-knife cutting system 111 is arranged symmetrically about a knife plane 150; the knife bar 110 is further located at the level of the double-knife cutting system 111. In the direction of an axis 170 orthogonal to the knife plane 150, the knife bar comprises a first extension 112. Sections of the knife back 144, 184 adjacent to a gap 160 between the knife bar 110 and the double-knife cutting system 111 are bent symmetrically in the direction of the orthogonal axis 170 with respect to the knife plane 150. The knife backs 144, 184 shown in FIG. 2 are bent such that a distance 113 between protruding parts of the bent knife backs 144, 184 is greater than the first extension 112 of the knife bar 110: this partially shields the gap 160. The bending of the sections of the knife back 144, 184 adjacent to the gap 160 can also be configured such that the distance 113 is equal to the first extension 112. The bending angle 155 shown in FIG. 2 is to be understood only schematically and can be between 5? and 45? and preferably equal to 15?.

[0041] FIG. 3 shows a perspective view of a mower knife device 100 according to the invention, comprising a double-knife cutting system 111, a knife bar 110 and holding devices 115 for connecting the knife bar 110 to the double-knife cutting system 111, wherein a gap 160 is present between the double-knife cutting system 111 and the knife bar 110. As shown schematically in FIG. 3 using the striped areas, the knife back 144 of the upper cutting knife 140 is bent upwardly in a section adjacent to the gap 160 and the knife back 184 of the lower cutting knife 180 is bent downwardly in the section adjacent to the gap 160. The bending of the sections of the knife backs 144, 184 adjacent to the gap 160 is uniform along the entire width of the double-knife cutting system 111.