Cutting system for a cutting unit

Description

1 / 23 CUTTING SYSTEM FOR A CUTTING UNIT

[001] The application relates to a cutting system for a cutting unit of an agricultural machine comprising a finger-holder bar with finger guards fixed to it, wherein the finger guards are positioned at a distance A from each other, and a knife with knife blades fixed to a knife rail, wherein the knife is guided alternately in relation to the finger guard, wherein the knife blades have a blade pitch T and wherein the knife performs an alternating motion with a stroke H.

[002] US patent 6,510,681 B2 describes a cutting system with knife blades attached to a knife rail. Sickle-shaped guard fingers provide a cutting surface for the knives during horizontal forward and backward movement. According to one embodiment of the cutting system, a combination of a four-and-a-half-inch stroke, a three-inch distance from the guard fingers, and a two-and-a-quarter-inch distance from the knife blades is described.

[003] When cutting crops with these cutting systems, the knife blades first push the crop laterally to the next finger guard, where the counter-blade is formed in order to cut the crop. The combination of the blade pitch T, the knife stroke H, and the distance A of the finger guards, among other factors, influences the performance of the cutting system.

[004] One objective may be to propose a cutting system that is improved in terms of blade pitch T and knife stroke H.

[005] The object is achieved by the subject matter in accordance with claim 1. The embodiments are specified in the dependent claims.

[006] The cutting system for a cutting unit of an agricultural machine comprises a finger-holder bar with guards for Petition 870250087616, dated 09 / 26 / 2025, page 8 / 47 2 / 23 fingers fixed to the same, wherein the finger guards are positioned at a distance A from each other, and a knife with knife blades fixed to a knife rail, wherein the knife is guided alternately in relation to the finger guard, wherein the knife blades have a blade pitch T and wherein the knife performs an alternating motion with a stroke H. The stroke H corresponds to at least one and a half times, or 1.5 times, the blade pitch T. The blade pitch T has a value between 58.5 millimeters and 63.5 millimeters.

[007] The finger guards are positioned at a distance To each other. According to one embodiment, the distance A corresponds to the blade pitch T. Compared to the state of the art, the small distance A of the finger guards reduces the achievable filling area relative to the blade length, i.e., the area between the knife blades that can be filled with crop. The number of cutting edges is also increased relative to the blade length, since two cuts are made per stroke. Tests with different combinations of blade pitch T, knife stroke H, and distance A between the finger guards showed that, with comparable loads on the knife drive mechanism and comparable crop properties to be cut, particularly high rotational speeds of the combine harvester drive mechanism can be achieved with a blade pitch T between 58.5 mm and 63.5 mm due to the increased performance of the cutting system.This results in an increase in production per hectare, that is, in the area harvested in hectares per hour, with a cutting unit of the same width, or in the possibility of achieving comparable area production using an implement with a smaller working width than with prior art systems.

[008] According to one embodiment, the blade pitch T has a value of approximately 61 millimeters. This value corresponds to Petition 870250087616, dated 09 / 26 / 2025, p. 9 / 47 3 / 23 is approximately 2.4 inches. Common cutting units are divided into five-foot (5 ft) long segments in the longitudinal direction. 60 knife blades with a 2.4-inch T-blade pitch also advantageously extend along the length in the longitudinal direction of five feet.

[009] For example, the H stroke corresponds to 1.9 to 2.1 times the T blade pitch. With a 2.4-inch blade pitch, this corresponds to an H stroke between 115.8 millimeters and 128.0 millimeters. For example, the H stroke is 122.2 millimeters or twice the T blade pitch. The theoretical value of twice the H stroke compared to the T blade pitch for a cutting system that cuts twice per stroke is generally not necessary in practice, since the second cut per stroke is already completed as soon as a front edge of the cutting edge passes through a corresponding counter-cutting edge on the finger guard.

[0010] According to another embodiment, the T-blade pitch has a value of approximately 61 millimeters. This value corresponds to about 2.4 inches. Tests have demonstrated the highest production value of the cutting unit per hectare with this blade pitch. According to another embodiment, the T-blade pitch has a value of approximately 61 millimeters.

[0011] According to another embodiment, the knife has a mass M of less than 20 g / cm in relation to its length along a longitudinal axis, in particular less than 18 g / cm and, particularly preferably, about 15.85 g / cm, which corresponds to 1.07 pounds per foot (lb / ft). The mass of the knife includes the blades, the back of the knife and the fastening elements for mounting the blades on the back of the knife. The connecting section or cutting head intended for connection to the drive mechanism is not included in the mass M of the knife in relation to its length along the axis. Petition 870250087616, dated 09 / 26 / 2025, p. 10 / 47 4 / 23 longitudinal.

[0012] For example, each knife blade has a centerline, where the knife blades are positioned close to each other along a longitudinal axis of the cutting system. The blade pitch T can be defined as the distance between the centerlines of two adjacent knife blades. The centerlines are orthogonal to the longitudinal axis and divide the knife blade into two halves. Finger guards may each have a fingertip, where the finger guards are positioned close to each other along the longitudinal axis. The distance A can be defined as the distance between the fingertips. With multiple blades, a plurality of blades is made in one piece, such as the so-called double blade or triple blade. Multiple blades have a centerline per knifetip. The blade pitch T refers to the individual blades, not the multiple blade as a whole.In the case of multiple finger guards, a plurality of finger guards is designed in one piece, such as so-called double fingers or triple fingers. Multiple cutting fingers have one fingertip per finger guard. Distance A refers to the individual finger guards, not to the multiple finger guards as a whole. Distance A may correspond to blade pitch T, where the finger guards may be provided in at least two variants of different finger lengths in the working direction.

[0013] According to another embodiment, a drive mechanism is foreseen to actuate the knife, wherein the rotational speed of the drive mechanism is, for example, between 450 and 750 revolutions per minute, and the knife performs one of the alternating movements with the H-stroke for each rotation of the drive mechanism. The rotational speed of the drive mechanism may be about 540 revolutions per minute, wherein the knife then performs about Petition 870250087616, dated 09 / 26 / 2025, page 11 / 47 5 / 23 of 1080 movements per minute. Especially when mowing grass, the rotation speed of the drive mechanism can be around 700 to 750 revolutions per minute.

[0014] According to another embodiment, the load on the drive mechanism, due to the centrifugal force of the knife at a drive mechanism speed of 540 revolutions per minute, is provided to be less than or equal to the load on the drive mechanism due to the centrifugal force of a reference knife of a reference cutting system at drive mechanism speeds of 600 revolutions per minute. More generally, the speed of the drive mechanism may be 90% of the speed of the drive mechanism of the reference cutting system. The reference cutting system corresponds to the claimed cutting system in terms of properties influencing the load on the drive mechanism, except for the following parameters of the reference cutting system: - a Tref blade pitch of 76.2 millimeters or 3 inches, - an Href stroke of 84.6 millimeters or 3.33 inches, - a reference knife mass (Mref) relative to its length along the longitudinal axis of at least 21 g / cm, in particular 22.33 g / cm or 1.5 pounds per foot (lb / ft).

[0015] The load on the drive mechanism should be understood as a theoretical load due to the centrifugal force of the knife or the reference knife at idle speed, i.e., without cutting the harvest and without taking friction into account. The reference cutting system corresponds to the claimed cutting system in relation to all properties, except for the specified parameters and the properties arising from the parameters. For example, the reference cutting system with a Tref blade pitch of 76.2 millimeters or 3 Petition 870250087616, dated 09 / 26 / 2025, page 12 / 47 A 6 / 23 inch blade has a smaller number of blades with identical width to that of the cutting unit. For a 5-foot-wide cutting unit segment, the reference blade has 48 blades, while the blade of the claimed cutting system may have 60 blades. Regarding properties not associated with the divergent parameters, the reference cutting system corresponds to the claimed cutting system. For example, the kinematics of the drive mechanism used are identical. The load is related to the blade length in the longitudinal direction and is, for example, 3.73 N / cm or 113.69 newtons per foot (N / ft) for the reference blade.

[0016] According to another embodiment, the finger guards are made of a sheet of metal. The finger guard may have an opening for the blade that forms counter-blades for the knife blades. Compared with a forged finger, the finger guard with an opening for the blade made of sheet metal does not have a fastening device. According to another embodiment, the finger guards may be provided in at least two variants, with different finger lengths in the working direction. The cutting fingers of the shorter variant or all the cutting fingers may be open at the knife tip, so that the knife tips may project beyond the finger guard.

[0017] Knife blades have an upper side and a lower side. A surface on the underside may consist of a flat surface positioned in a plane and a recessed area extending above the plane, where the height of the knife blade corresponds to a maximum distance between the upper side and the flat surface in the direction normal to the plane. The thickness of the knife blade material may be less than the height of the knife blade, at least in some areas, where the thickness of the knife blade material corresponds to a distance between the upper side and the lower side. Petition 870250087616, dated 09 / 26 / 2025, p. 13 / 47 7 / 23 knife blades can therefore be advantageously produced with a reduced mass and the same knife blade height.

[0018] According to another embodiment, it is foreseen that the knife blades can be fixed to the knife rail either with the upper side facing the knife rail or with the lower side facing the knife rail.

[0019] An upper lateral surface may, for example, consist of a flat upper surface positioned on an upper plane and an upper area extending outward from the upper plane. The surface of the upper face adjacent to a rear edge of the respective knife blade may be formed, at least in sections, by the flat upper surface. This means that part of the flat upper surface of the upper face is in contact with the knife rail. Knife blades may be fixed to the knife rail alternately, with the upper face facing the knife rail and the lower face facing the knife rail.

[0020] According to another embodiment, knife blades are expected to have a constant blade angle with a value between 20° and 27°. The blade angle corresponds to half the angle formed by the blade tip. A perpendicular to the longitudinal axis in a plane of the knife blade and a straight line along a cutting edge of the knife blade encircle the blade angle. The blade angle is 21°, for example. Furthermore, knife blades may have, section by section, a first constant blade angle and a second constant blade angle that differs from the first blade angle, wherein the transition between sections may be discontinuous at a point of curvature. Alternatively, the transition between sections may be gradual so that, at least in the area of ​​a transition section, the cutting edge is curved without a constant blade angle. Petition 870250087616, dated 09 / 26 / 2025, page 14 / 47 8 / 23

[0021] According to another embodiment, knife blades have two cutting bevels, wherein one of the cutting bevels is located on the upper part and the other bevel is located on the lower part. In particular, the cutting bevels may completely overlap in the vicinity of the knife tip. Since the cutting bevels are located on different sides of the knife blade, overlapping is possible. The overlap advantageously results in a narrower knife tip and, with the same blade angle, in a greater length of the cutting section in the working direction of the knife blade. The knife may have knife blades in at least two variants, with different lengths of the cutting section in the working direction and / or different blade angles.

[0022] Exemplary embodiments are described below with reference to the accompanying drawings. The explanations do not restrict the general idea of ​​the invention.

[0023] In the Figures: Figure 1 shows a partial view of a cutting system according to one of the methods; Figure 2 is a side view of the cutting system as shown in Figure 1; Figure 3 is a partial view of a knife from the cutting system as shown in Figure 1; Figure 4 is a partial view of a cutting system according to another method; Figure 5 is a partial view of a knife from the cutting system as shown in Figure 4; Figure 6 is a partial view of an unclaimed reference cutting system; Figures 7 to 11 show a knife blade for the cutting system in different views; Petition 870250087616, dated 09 / 26 / 2025, page 15 / 47 9 / 23 Figures 12 and 13 show a variant of the knife blade in different views; Figures 14 and 15 show another variant of the knife blade in different views; Figures 16 to 18 show another variant of the knife blade in different views; Figure 19 is a comparative illustration of variants of the knife blades shown in Figures 12, 14 and 16; Figure 20 is a diagram showing a comparison of the achievable travel speeds with the knife blade variants shown in Figure 19; and Figure 21 is another diagram showing a comparison of the achievable travel speeds with the knife blade variants shown in Figure 19.

[0024] Figure 1 shows a partial schematic representation of a cutting system for a cutting unit of an agricultural machine. Figure 2 shows a side view of the cutting unit. Figure 3 shows a knife 14 of the cutting unit in detail. Figures 1 to 3 are described together below. The cutting system comprises a finger bar 19 with finger guards 18 fixed to it, wherein the finger guards 18 are positioned at a distance A from each other, and the knife 14 with knife blades 10 fixed to a knife rail 22, wherein the knife 14 is alternately guided relative to the finger bar 19, wherein the knife blades 10 have a blade pitch T and wherein the knife 14 performs an alternating motion with a stroke H. The distance A may correspond to the blade pitch T, while the stroke H corresponds to approximately twice the blade pitch T, which stroke may also be called double stroke.The T-blade pitch has a value between 58.5 millimeters and 63.5 millimeters. Petition 870250087616, dated 09 / 26 / 2025, p. 16 / 47 10 / 23

[0025] The knife blades 10 each have a knife point. 11, where knife blades 10 are positioned side by side along a longitudinal axis L. The blade pitch T is defined as a distance between center lines C orthogonal to the longitudinal axis L of two adjacent knife blades 10; see Figure 5. Finger guards 18 each have a fingertip 20, where the finger guards 18 are positioned side by side along the longitudinal axis L and where the distance A is defined as a distance between the fingertips. A drive mechanism 21 can drive the knife 14, wherein a rotational speed of the drive mechanism 21 is between 450 and 750 revolutions per minute and wherein the knife 14 performs one of the alternating movements with the stroke H for each revolution of the drive mechanism. The speed of the drive mechanism 21 can be 540 revolutions per minute, for example.

[0026] The knife 14 comprises, for example, a knife rail 22, also called a knife back 22. Several knife blades 10 are fixed to the knife rail 22. The knife blades 10 are positioned and fixed to the knife back 22 side by side along the longitudinal axis L. The knife back 22 is connected to a connecting section 25. The connecting section 25 is used to couple the knife 14 to the drive mechanism 21, which moves the knife 14 back and forth along the longitudinal axis L. The knife blades 10 can be connected to the knife back 22 by means of one or more fastening elements 26, such as screws and / or nuts. Persons skilled in the art will know other ways of fixing the knife 14.

[0027] The knife blades 10 each have a cutting section and a clamping section 9 with a trailing edge 8, which are positioned consecutively along a working direction P. A working direction P is perpendicularly aligned to Petition 870250087616, dated 09 / 26 / 2025, p. 17 / 47 11 / 23 longitudinal axis L and corresponds, for example, to the direction of travel of an agricultural machine. Viewed in the working direction P, the cutting sections 27 of the knife blades 10 project forward from the rear of the knife 22. The knife blades 10 are positioned in contact with the rear of the knife 22 by means of the fixing section 9. The rear edges 8 of the knife blades 10 may project backward, beyond the rear of the knife 22, in the working direction P. The cutting edges 3 are formed in the cutting section 27 of the respective knife blade 10 and are aligned at an angle to each other such that they point towards the working direction P. A straight line along the cutting edge 3 encloses a constant blade angle K with the working direction P, K being between 20 degrees and 27 degrees, in particular about 21 degrees.

[0028] In the embodiment shown, the knife blades 10 are all aligned in the same way, that is, with a lower side 2 facing the back of the knife 22. All upper sides 1 of the knife blades 10 are facing away from the back of the knife 22.

[0029] Figure 4 shows a schematic partial view of the cutting system according to another embodiment. Figure 5 shows the knife 14 of the cutting system shown in Figure 4. Figures 4 and 5 are described together. In Figure 5, the blade pitch T is indicated as the distance between the center lines C orthogonal to the longitudinal axis L of two adjacent knife blades 10. The structure largely corresponds to the embodiment shown in Figure 1 and is not described again. Identical components are marked with identical reference signs. The illustrated embodiment differs in the positioning of the knife blades 10. These are positioned alternately on the back of the knife 22. The upper side 1 and the lower side 2 are alternately facing the back of the knife 22.

[0030] Figure 6 shows schematically a cutting system. Petition 870250087616, dated 09 / 26 / 2025, p. 18 / 47 12 / 23 reference, unclaimed. The reference cutting system corresponds to the claimed cutting system in terms of properties influencing the load on the drive mechanism, except for the following parameters of the reference cutting system: - a Tref blade pitch of 76.2 millimeters or 3 inches, - a Href stroke of 84.6 millimeters or 3.33 inches, and - a reference knife mass Mref, relative to its length along the longitudinal axis, of at least 21 g / cm, in particular 22.33 g / cm or 1.5 pounds per foot (lb / ft).

[0031] The reference cutting system corresponds to the claimed cutting system with respect to all properties except for the specified parameters and the properties derived from the parameters. For example, the reference cutting system with a Tref blade pitch of 76.2 millimeters or 3 inches has a smaller number of blades with a width identical to that of the cutting unit. For a cutting unit segment 5 feet wide, the reference knife has 48 blades, whereas the knife of the claimed cutting system may have 60 blades. The reference cutting system corresponds to the claimed cutting system with respect to properties not associated with the divergent parameters. For example, the kinematics of the drive mechanism not shown here is identical.

[0032] A load on the drive mechanism 21 of the embodiments according to Figures 1 and 4 due to a centrifugal force of the respective knife 14 at a speed of the drive mechanism 21 of 540 revolutions per minute is less than or equal to the load on the drive mechanism due to the centrifugal force of a reference knife 14' of the reference cutting system according to Figure 6 at a speed of the drive mechanism of 600 revolutions per minute. Petition 870250087616, dated 09 / 26 / 2025, page 19 / 47 13 / 23

[0033] Figures 7 to 11 show another exemplary knife blade 10 in various views. In Figure 7, the knife blade 10 is shown in a view of the top 1. Figure 8 shows the knife blade of Figure 3 in a view rotated 90 degrees from the side, in which the position of the knife tip 11 at the front and the back edge 8 at the back, as well as the overall planar shape of the knife blade 10 with the top 1 and bottom 2 can be seen. Figure 9 shows a cutaway view along line AA of Figure 7, magnified twice. Figure 10 shows a view of the bottom 2 of the knife blade 10 and Figure 11 again shows a magnified view of the back edge 8 rotated 90 degrees relative to Figure 7.

[0034] Figures 7 to 11 are referred to together below. The knife blade 10 has two cutting edges 3 for cutting the crops, wherein the outer edge of each forms the border. At the tip of the knife 11, which is somewhat blunt in shape in the exemplary embodiment, the cutting edges 3 converge approximately and thus form the approximately triangular shape of the front part of the knife blade 10. This part of the knife blade 10 has an approximately triangular recess 5 with a surrounding border area 7. The direction of movement of the knife 14 with the knife blade 10 for cutting the crop is transverse to the working direction P (Figure 2), in particular approximately at right angles to it, horizontal or slightly inclined in the installation position, which corresponds to the drawing plane in Figure 3.The approximately triangular cutting section 27 of the knife blade 10 is joined by the fastening section 9, which has an approximately rectangular shape in view and ends with the rear edge 8. The fastening section 9 has fastening means 17 for mounting the knife blade 10 which is mounted on the knife bar (22, Figure 1). Petition 870250087616, dated 09 / 26 / 2025, page 20 / 47 14 / 23

[0035] The lower side surface 2 consists of a flat surface 4 positioned on plane E (see Figure 7) and the recessed area 6 extending above plane E, as can be seen in Figures 5 and 6. The height Z of the knife blade 10 corresponds to the maximum distance between the upper side 1 and the flat surface 4 in a direction normal N to plane E, as shown in Figure 7. An upper side surface 1 again consists of an upper flat surface 15 positioned on an upper plane OE (Figure 7) and an upper area 16 extending outward from the upper plane OE. The material thickness M of the knife blade 10 corresponds to the distance between the upper side 1 and the lower side 2, which is measured in the normal direction N. The material thickness M of the knife blade 10 is, at least in some areas, less than the height Z of the knife blade 10, as shown by way of example at a measurement point in Figure 11.The lower plane E and the upper plane OE are preferably aligned parallel to each other and spaced by the height Z of the knife blade 10.

[0036] The flat surface 4 can be a surface whose planarity, also called flatness, is greater than that of the recess area 6. Any points on the flat surface 4 are therefore spatially positioned in plane E. The recess area 6 also forms a surface that can be irregular by comparison, i.e., curved or arched, so that points on the surface of the recess area 6 are spatially positioned in different planes. The flat surface 4 comprises several partial surfaces. In the cutting edge area 3 of the knife blade, the lower side surface 2 has a partial surface 4A of the flat surface 4. On the lower side surface 2, wear marks 12 can be located directly on the partial surface 4A located in the cutting edge area 3 to determine the wear on the edge of Petition 870250087616, dated 09 / 26 / 2025, page 21 / 47 15 / 23 cut. Another partial surface 4B of the flat surface 4 of the underside surface 2 is located around the recess 5, in the area of ​​the edge 7 of the recess 5. On the rear edge 8 of the knife blade, a plurality of partial surfaces 4C of the flat surface 4 are located on the underside surface 2. Finally, a partial surface 4D of the flat surface 4 is located on the clamping section 9.

[0037] A plurality of upper partial surfaces 15C of the upper flat surface 15 is preferably located on the rear edge 8 of the knife blade on the upper side surface 1, where the upper partial surfaces 15C are each located opposite the recessed area 6 on the rear edge 8 on the lower side 2. The upper partial surfaces 15C are each interrupted along the rear edge 8 by the upper area 16, where the partial surfaces 4C on the lower side 2 are each opposite the upper area 16, so that the upper partial surfaces 15C are located along the rear edge 8 alternately with the partial surfaces 4C on the lower side 2. This allows the knife blade 10 to be mounted with the lower side 2 facing the knife bar (22, Figure 2) as well as with the upper side 1 facing the knife bar.The reduced area on the rear edge 8, which results from the recognizable waveform in Figure 11, also advantageously reduces friction with respect to the guide elements (not shown) that support the knife blade 10 at the rear.

[0038] Figures 12 and 13, described together, show a variant of knife blade 10 in a side and perspective view. The illustration is diagrammed and serves to explain the modalities of the cutting edges 3. The characteristics of the surfaces and the rear cutting edge, as shown in Figures 7 to 11, are not shown here, but can be combined with the characteristics described below. Knife blade 10, as shown in Figures 12 and Petition 870250087616, dated 09 / 26 / 2025, p. 22 / 47 16 / 23 13, has cutting section 27 with two cutting edges 3 and fastening section 9 with holes as fastening means 17. A cutting chamfer 28 of each cutting edge 3 is provided only on the upper part 1. The cutting chamfers 28 form the cutting edge on the outer edge, together with the lower part 2 of the knife blade. The blade angle K is between 20 and 27 degrees.

[0039] Figures 14 and 15, described together, show another variant of the knife blade 10 in a side and perspective view. The surface and back edge features, as shown in Figures 7 to 11, are not shown here, but can be combined with the features described below. The knife blade 10, as shown in Figures 14 and 15, has the cutting section 27 with two cutting edges 3 and the fastening section 9 with holes as fastening means 17. The cutting chamfers 28 of the cutting edges 3 are provided only on the upper part 1 of the knife blade 10 and each has a bending point 29. The cutting chamfers 28 form the cutting edge on the outer edge, together with the lower part 2 of the knife blade. A first constant blade angle K1 of 21 degrees, for example, is less acute than a second constant blade angle K2 of 15 degrees, for example.

[0040] Figures 16 to 18, described together, show another variant of the knife blade 10 in a side and perspective view. The surface and back edge features, as shown in Figures 7 to 11, are not shown here, but can be combined with the features described below. The knife blade 10, as shown in Figures 14 and 15, has the cutting section 27 with two cutting edges 3 and the fastening section 9 with holes as fastening means 17. One of the cutting chamfers 28 is located on the upper part 1 of the knife blade 10 and forms the cutting edge on the outer edge, together with the lower part 2 of the knife blade 10, Petition 870250087616, dated 09 / 26 / 2025, page 23 / 47 17 / 23 while the other cutting bevel 28 is located on the lower part 2 of the knife blade 10 and forms the cutting edge on the outer edge, together with the upper part 1 of the knife blade 10. The two cutting edges are therefore positioned offset in different planes in the normal direction. The at least partial overlap of the cutting bevels 28 in the knife tip area 11 advantageously allows for a narrower knife tip 11 than in the knife blade 10, according to Figure 12. The blade angle K is approximately 21 degrees, where the exemplary embodiment is not restricted by this. Preferably, the knife blade 10 has a constant blade angle K between 20 degrees and 27 degrees.

[0041] Figure 19 shows a comparative illustration of variants of knife blades 10. The knife blade identified as 10A has a blade angle K of 21 degrees and a blade pitch T of two inches, which corresponds to the extension of the knife blade in the longitudinal direction L (see Figure 5). Knife blade 10A cannot be used with the cutting unit according to the invention. 10B indicates the knife blade shown in Figure 12, which has a blade angle K of 21 degrees and a blade pitch T of 2.4 inches. The length LP of the cutting section 27 in the working direction P is greater for knife blade 10B than for knife blade 10A with the same blade angle K. 10D denotes the knife blade shown in Figure 16, which has a blade angle K of 21 degrees and a blade pitch T of 2.4 inches.Due to the overlapping of the cutting bevels 28 in the knife tip area 11, the length LP of the cutting section 27 in the working direction P is greater for knife blade 10D than for knife blade 10B with the same blade angle K. 10C indicates the knife blade as shown in Figure 14, which has a first blade angle K1 of 21 degrees and a second blade angle K2 of 15 degrees. The blade pitch T is... Petition 870250087616, dated 09 / 26 / 2025, page 24 / 47 18 / 23 of 2.4 inches. Due to the sharper blade angle K2, the length LP of the cutting section 27 in the working direction P is greater than that of knife blades 10B and 10D. The second sharper blade angle K2 leads to less favorable cutting behavior of knife blade 10C in this area.

[0042] Figure 20 shows a diagram for the comparative representation of the achievable travel speeds for the knife blade variants shown in Figure 19. The abscissa 30 shows the stroke H in millimeters. An achievable travel speed of a combine harvester is shown dimensionless on the ordinate 31. Curve profiles 32, 33, 34 and 35 show that the achievable travel speed increases progressively with the stroke H, where the characteristics of the respective curve depend on the number of cutting edges per stroke and the blade shape. To make the different blade shapes comparable, the load on the drive mechanism was standardized by the centrifugal force of the knife.

[0043] Curve profile 32, shown with dots, represents the relationship between travel speed and stroke H for a cut per stroke. Point 36 in curve profile 32 indicates the travel speed achievable with a commonly used knife blade of a single-cut reference cutting system with a blade pitch of 3 inches and a blade angle of 30 degrees, with a stroke H of approximately 3.33 inches or 84.6 millimeters, which cannot be used with the claimed cutting system, but rather, for example, with the reference cutting system according to Figure 6. The achievable travel speed of the reference cutting unit is 100%.

[0044] Curve profile 33, shown with short dashes, represents the relationship between the travel speed and the stroke H for two cuts per stroke. Point 37 on curve profile 33 indicates the speed Petition 870250087616, dated 09 / 26 / 2025, page 25 / 47 19 / 23 of the achievable displacement of 162% of the reference cutting system with a commonly used knife blade with a 2-inch pitch and a K-blade angle of 21 degrees, with an H-stroke of 4 inches or 101.6 millimeters, which is given as an example for comparison and cannot be used with the claimed cutting system. Point 38 on curve profile 33 indicates the achievable displacement speed of 182% with knife blade 10B according to Figures 12 and 19, which can be used with the claimed cutting system. Knife blade 10B has a T-pitch of 2.4 inches and a K-blade angle of 21 degrees, with an H-stroke of 4.8 inches or 121.9 millimeters. If the H-stroke is less than twice the blade pitch in practice, the achievable displacement speed will be correspondingly lower on curve profile 33.

[0045] Curve profile 34, shown with long lines and dots, represents the relationship between travel speed and stroke H for two cuts per stroke. Point 39 on curve profile 34 indicates the achievable travel speed of 210% with knife blade 10C, according to Figures 14 and 19, which can be used with the claimed cutting system, with a blade pitch of 2.4 inches, a first blade angle K1 of 21 degrees and a second blade angle K2 of 15 degrees, with a stroke H of 4.8 inches or 121.9 millimeters. If the stroke H is less than twice the blade pitch in practice, the achievable travel speed will be correspondingly lower on curve profile 34.

[0046] The curve profile 35 shown with medium-length lines represents the relationship between the travel speed and the stroke H for two cuts per stroke. Point 40 on the curve profile 35 denotes the achievable travel speed of 196% of the 10D knife blade usable with the claimed cutting system according to Figures 16 and 19, with a blade pitch of 2.4 inches and Petition 870250087616, dated 09 / 26 / 2025, page 26 / 47 20 / 23 has a 21-degree blade angle on a 4.8-inch or 121.9-millimeter H-stroke. The achievable travel speed is lower than with the 10C knife blade, but its sharp 15-degree K2 blade angle results in worse cutting behavior. If the H-stroke is less than twice the blade pitch in practice, the achievable travel speed is correspondingly lower on the 35 curve profile.

[0047] Figure 21 shows an additional diagram comparing the achievable travel speeds with the knife blade variants shown in Figure 19. The abscissa 30' shows the H-stroke in millimeters, the respective H-strokes being identical to those in Figure 20. The ordinate 31' shows an achievable travel speed without dimensions. The load on the drive mechanism is the same for all variants shown, allowing a relative comparison. For the curve profiles 33', 34', and 35' of the knife blades according to Figure 19, a 30% mass reduction is considered compared to the corresponding curve profiles 33, 34, and 35 in Figure 20. The curve profile 32 of the reference system remains unchanged. Point 36 on curve profile 32 indicates the achievable travel speed of the single-cut reference cutting unit of 100%.

[0048] Point 37' on curve profile 33' indicates an achievable travel speed of 195% with knife blade 10A according to Figure 19, which cannot be used with the claimed cutting system, considering a 30% mass reduction with identical parameters. Point 38' on curve profile 33' indicates an achievable travel speed of 217% with knife blade 10B, according to Figures 12 and 19, considering a 30% mass reduction with identical parameters. Point 39' on curve profile 34' indicates an achievable travel speed of 251%. Petition 870250087616, dated 09 / 26 / 2025, page 27 / 47 21 / 23 with knife blade 10C according to Figures 14 and 19, taking into account a 30% mass reduction with identical parameters. Point 40' on curve profile 35' indicates the achievable travel speed of 234% of knife blade 10D according to Figures 16 and 19, taking into account a 30% mass reduction with identical parameters. If the stroke H is less than twice the blade pitch T in practice, the achievable travel speed will be correspondingly lower on the respective curve profiles 33', 34' and 35'. Reference numbers Top side Bottom side Tip Flat surface 4A Partial surfaces of the plane surface 4B Partial surfaces of the plane surface 4C Partial surfaces of the plane surface 4D Partial surfaces of a flat surface Recesses Recess area Recess border area Back edge of the knife blade Fastening section Knife blades Knife point Signs of wear Do 14' Reference knife Top flat surface 15C Upper partial surfaces of the upper flat surface Petition 870250087616, dated 09 / 26 / 2025, page 28 / 47 22 / 23 on the back edge Upper area Fastening methods, hole Finger guard finger holder bar Fingertip Actuation mechanism Knife rail, back part of the knife Connection section Fastening element, screw, nut Cutting section Beveled cut Point of curvature Abscissa Ordered Curve profiles Curve profiles Points Points Longitudinal axis Course Step Distance Center line Reference course Reference step Reference distance Top view Flat Normal direction Petition 870250087616, dated 09 / 26 / 2025, page 29 / 47 23 / 23 Z Knife blade height Work Direction M Material thickness K Blade angle K1 First blade angle K2 Second blade angle LP Length of the cutting section in the working direction Petition 870250087616, dated 09 / 26 / 2025, page 30 / 47

Claims

1 / 4 CLAIMS 1. Cutting system for a cutting unit of an agricultural machine, characterized in that it comprises: - a finger-holder bar (19) with finger guards (18) fixed thereto, - a knife (14) with knife blades (10) fixed to a knife rail (22), wherein the knife is guided alternately in relation to the finger-holder bar, wherein the knife blades have a blade pitch T and wherein the knife performs an alternating motion with a stroke H, wherein the stroke H corresponds to at least one and a half times the blade pitch T and wherein the blade pitch T has a value between 58.5 millimeters and 63.5 millimeters.

2. Cutting system, according to claim 1, characterized in that the blade pitch T has a value of 61 millimeters or 2.4 inches, wherein the stroke H is greater than the blade pitch T by a factor between 1.9 and 2.

1.

3. Cutting system, according to any of the preceding claims, characterized in that the knife has a mass M of less than 20 g / cm in relation to its length along a longitudinal axis (L), in particular less than 18 g / cm and, particularly preferably, less than 16 g / cm.

4. Cutting system, according to any of the preceding claims, characterized in that the knife blades (10) each have a center line (C), wherein the knife blades are positioned side by side along a longitudinal axis (L) of the cutting system, wherein the blade pitch T is defined as a distance between the center lines of adjacent knife blades.

5. Cutting system, according to claim 4, characterized in that the finger guards (18) each have a fingertip (20), wherein the finger guards are positioned side by side along the longitudinal axis (L), wherein the finger guards are each positioned at a distance A from each other, wherein the distance A is defined as a distance between the fingertips, wherein the distance A corresponds in particular to the blade pitch T and wherein the finger guards are provided in at least two variants of different finger lengths in the working direction.

6. Cutting system, according to any of the preceding claims, characterized in that a drive mechanism (21) drives the knife (14), wherein the rotational speed of the drive mechanism is between 450 and 750 revolutions per minute and wherein the knife performs an alternating motion with the stroke H for each revolution of the drive mechanism.

7. Cutting system, according to claim 6, characterized in that a load on the drive mechanism (21) due to a centrifugal force of the knife (14) at a drive mechanism rotation speed of 90 percent of a drive mechanism rotation speed of a reference cutting system is less than or equal to the load on the drive mechanism (21) due to the centrifugal force of a reference knife of the reference cutting system, wherein the reference cutting system corresponds to the cutting system with respect to the properties influencing the load on the drive mechanism, except for the following parameters of the reference cutting system: - a blade pitch Tref of 76.2 millimeters or 3 inches, - a stroke Href of 84.6 millimeters or 3.33 inches, - a mass Mref of the reference knife, with respect to its Petition 870250087616, dated 09 / 26 / 2025, p.32 / 47 3 / 4 length along the longitudinal axis (L), of at least 21 g / cm, in particular 22.33 g / cm or 1.5 lb / ft.

8. Cutting system, according to any of the preceding claims, characterized in that the knife blades (10) have an upper side (1) and a lower side (2), wherein the knife blades can be fixed to the knife rail (22) either with the upper side facing the knife rail or with the lower side facing the knife rail, wherein the knife blades (10) are fixed to the knife rail (22) in particular alternately with the upper side (1) facing the knife rail (22) and with the lower side (2) facing the knife rail.

9. Cutting system, according to claim 8, characterized in that a lower side surface (2) consists of a flat surface (4) positioned in a plane (E) and a recess area (6) extending above the plane, wherein a knife blade height (10) corresponds to a maximum distance (Z) between the upper side and the flat surface in a direction normal (N) to the plane.

10. Cutting system, according to claim 9, characterized in that the thickness of the knife blade material (10) is, at least in some areas, less than the height (H) of the knife blade, wherein the thickness of the knife blade material corresponds to a distance between the upper side (1) and the lower side (2).

11. Cutting system, according to any of the preceding claims, characterized in that the knife blades (10) have a constant blade angle (K), wherein the blade angle (K) has a value between 20° and 27°.

12. Cutting system according to claim 11, characterized in that the blade angle (K) has a value of approximately 21°. Petition 870250087616, dated 09 / 26 / 2025, page 33 / 47 4 / 4 13. Cutting system, according to any of the preceding claims, characterized in that the knife blades (10) have, section by section, a first constant blade angle (K1) and a second constant blade angle (K2) different from the first blade angle (K1).

14. Cutting system, according to any of the preceding claims, characterized in that the knife blades (10) have an upper side (1) and a lower side (2), wherein two cutting bevels (28) are provided and wherein one of the cutting bevels is located on the upper side and the other cutting bevel is located on the lower side.

15. Cutting system according to claim 14, characterized in that the cutting bevels (28) completely overlap in the vicinity of a knife tip (11). Petition 870250087616, dated 09 / 26 / 2025, pp. 34 / 47

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