Harvesting machine comprising a conveying rotor with rotor tines having a circumferentially extending flattening at the tine end

Description

[0001] The present invention relates generally to harvesting machines that convey harvested crops through a conveying channel into a storage and / or pressing chamber by means of a conveying rotor. The invention relates to... one Harvesting machine whose conveying rotor has conveying tines that protrude with respect to a rotor axis of rotation and, when viewed in the direction of the rotor axis of rotation, taper from a root section to a projecting tine end.

[0002] Such conveying rotors are used, for example, in forage wagons or balers to transport the crop picked up from the ground by the pickup through a conveying channel into the loading chamber of the forage wagon or the pressing chamber of the baler. The conveying rotor can rotate around a horizontal axis of rotation extending transversely to the direction of travel and typically has a large number of conveying tines arranged in several rows distributed around its circumference. These rows can be parallel to the axis of rotation, slightly helical around the axis, or intersected in some other way. Across the width of the rotor, or along the axis of rotation, a large number of conveying tines are usually arranged side by side and spaced apart from one another to ensure sufficient conveying efficiency across the entire width of the rotor.

[0003] The conveying rotor can be assigned a cutting unit that can include several knives projecting into the conveying channel, which plunge into the spaces between adjacent conveying tines, so that the passing conveying tines drive the harvested crop onto the knives and cut it there.

[0004] The aforementioned conveying channel, independent of the aforementioned cutting unit, is bounded along the outer circumference of the conveying rotor by a retaining wall that encloses a sector of the rotor in a trough-like manner or hugs the rotor's outer circumference, preventing the crop from being unintentionally stripped from the rotor tines. This retaining wall can, for example, be made of sheet metal and have slot-shaped openings through which the cutting unit's knives can enter the cutting channel.

[0005] The conveying tines of the feed rotor are subject to a variety of requirements to ensure the crop is transported through the conveying channel as gently and efficiently as possible. On the one hand, a stable and powerful conveying action is required in the cutting unit area to reliably transport the crop past the cutting knives and achieve the desired cutting effect. On the other hand, the crop should be easily stripped from the conveying tines in the rotor's discharge area to ensure a reliable flow into the loading or baling chamber. In any case, blockages or chopping, resulting in uneven running and excessive reaction forces, must be avoided.

[0006] To meet these diverse requirements, the conveying tines often have a saber-shaped contour that tapers to a point at the tip. The leading edge of the tine, in the direction of rotation, curves backward, meaning it is bent outwards away from the rotor axis, against the direction of rotation. This prevents the tines from being too aggressive and ensures smooth penetration and conveying. It is important to note that the conveying speed of the rotating rotor tines increases towards the tips due to the increasing radius. Simultaneously, the gap between the projecting tine ends and the wall surrounding the conveying channel plays a crucial role. A certain gap is necessary, but it must not be too large, as otherwise the conveying efficiency in the area of ​​the rapidly rotating tine tips would be compromised.

[0007] To ensure gentle penetration of the conveying tines into the inflow of the harvested crop flow, which usually comes from the pickup, the conveying tines typically taper to a more or less sharp point towards the projecting tine end, or the tine ends are often only rounded under a small radius to minimize resistance during penetration.

[0008] Conveyor rotors with such conveying tines, which taper to a point towards the projecting tine end, are known, for example, from US 2016 / 366827 A1, DE 203 083 69 U1 or EP 0 659 332 A1.

[0009] For specific applications, other conveying tines have also been proposed, for example, with protruding noses at the outer end of the tines in the conveying direction, in order to achieve sufficient conveying efficiency with difficult-to-convey materials such as short-cut straw (see DE 10 2016 217 609 A1). Furthermore, trapezoidal conveying tines are generally known from US 2008 / 290 198 A1, in order to use knives with variable penetration depth. However, this is generally detrimental to feed-friendly, energy-efficient conveying and leads to uneven running with a risk of clogging and high penetration resistance. Similar trapezoidal conveying tines are also used in DE 36 40 317 A1 and DE 33 34 045 A1.

[0010] Due to the constant relative movement and friction between the crop and the conveying tines, the tines are subject to continuous wear. This wear increases when a cutting unit is used due to the rising conveying resistance, especially when many blades are used for a short crop length. Contaminants in the crop, such as clods of earth, sand, or stones, further increase wear on the conveying tines.

[0011] Wear on the projecting tine ends is particularly critical when the conveying tines become shorter due to wear, thereby increasing the gap between the tine ends and the retaining wall that borders the conveying channel. If the gap becomes too large, the conveying efficiency decreases. At the same time, material buildup between the conveying tines and the retaining wall can cause blockages, especially when processing moist crops with higher friction against the retaining wall.

[0012] Based on this, the present invention aims to create an improved harvesting machine and an improved conveying rotor for it, avoiding the disadvantages of the prior art and advantageously developing the latter further. In particular, the conveying rotor should ensure permanently low-resistance, reliable and gentle conveying of the harvested crop without the need for complex wear protection measures such as special hardening or surface coating, and without the risk of blockages, high penetration resistance and difficult stripping.

[0013] According to the invention, the aforementioned problem is solved by a harvesting machine according to claim 1. Preferred embodiments of the invention are the subject of the dependent claims.

[0014] It is therefore proposed to widen the rotor's conveying tines in the head region or to lengthen them in the direction of rotation in order to maintain the tine length even as tine wear begins at the leading edge and to prevent an unwanted increase in the gap between the tine end and the conveying channel's retaining wall. According to the invention, the projecting tine end has a blunt tine head with a circumferential flattening that gives the projecting tine end, when viewed along the rotor's axis of rotation, a width in the range of approximately 30% to 200% of the conveying tine's material thickness. The aforementioned width of the head end refers to its extent in or tangential to the direction of rotation or to a tangent on the aforementioned flattening when the tine is viewed along the rotor's axis of rotation.

[0015] The aforementioned widening of the tine head relative to the material thickness of the conveying tine is based on the consideration that the thickness of the conveying tine significantly influences wear on the tine and is also subject to certain boundary conditions. In principle, wear could be counteracted by making the tine increasingly thicker. However, this would not only impair the tine's penetration into the crop flow at its inlet but also increase the tine's weight. This would be particularly problematic in the area of ​​the projecting tine ends, where higher rotational speeds and a greater moment of inertia due to the radius would disrupt the smooth running of the conveying rotor.If the conveying tine is widened at its projecting end, so that it no longer tapers to a point in the conventional manner but has a blunt, flattened end, the wear that is unavoidable with reasonable tine thicknesses can be compensated for or neutralized without affecting the gap to the enclosure wall. This is because the tine does not shorten due to the widened head, even with wear, but essentially retains its length. While the wear that typically begins at the leading edge, towards the projecting end of the tine, does further round off the leading edge, the widened, flattened head prevents this from shortening the tine, at least initially. Therefore, the gap remains unchanged, and the conveying effect is maintained.

[0016] On the other hand, by widening the tine end to between 0.3 and 2 times the material thickness, an excessive increase in penetration resistance in the feed of the conveyed material stream can be avoided.

[0017] The material thickness of the conveying tines can remain essentially constant along their length. If the conveying tine has a changing material thickness, particularly a slight decrease towards the tine tip, the aforementioned widening of the tine head can be related to the average material thickness in the outer half of the conveying tine.

[0018] In a further development of the invention, the width of the conveying tine at the tine head – when considering the conveying tine in the direction of the rotor axis of rotation – can be approximately 0.6 to 1.8 times the material thickness or approximately 0.8 to 1.5 times the material thickness. This allows for a particularly efficient compromise between maintaining the tine length during wear and, on the one hand, a feed-friendly conveying action with slight penetration at the feed point.

[0019] To prevent any impairment of the conveying effect, but also any excessive wear, between the conveying tine and the enclosing wall of the conveying channel that surrounds the rotor, isAccording to the invention, the width of the projecting tine end is adapted at its circumferential flattening to the gap dimension of the conveying rotor between its tine ends and the surrounding retaining wall of the conveying channel, and lies in the range of 10% to 100% of the stated gap dimension. In particular, it can preferably be 0.3 to 0.7 times the gap dimension. If the tine head is widened more than once the gap dimension, the penetration of the conveying tines into the crop becomes more difficult, and the excessively wide head forces the crop into the gap between the conveying tine end and the retaining wall, which can lead to blockages, excessive wear, and also crop contamination. Conversely, if the tine head is widened too little compared to the gap dimension, premature wear occurs, impairing the tine length and thus resulting in a loss of the desired conveying effect.

[0020] To maintain sufficient tine length even as the tines wear, while simultaneously ensuring that the tines do not excessively impede penetration into the crop flow, the aforementioned width of the conveying tine at the tine head can range from 3 mm to 30 mm. Specifically, the width at the tine head can be 8 mm to 25 mm or 10 mm to 20 mm.

[0021] The conveying tine can have fundamentally different contours along its path from the tine root to the tine head. In conjunction with the aforementioned head widening, it can be particularly advantageous if the conveying tine, viewed in the direction of the rotor axis of rotation, has an overall saber-shaped curvature with a convex leading edge, whereby the leading edge preferably extends continuously in a convex shape for at least one outer third of the conveying tine until it flattens out at the tine end. At the tine base or in the transition area to the rotor axis of rotation, the leading edge of the overall saber-shaped conveying tine can also be slightly concave to achieve a favorable transition to the rotor axis in terms of stress distribution and also to prevent the harvested crop from becoming stuck at the tine base.However, the leading edge of the conveying tine can be curved in a convex shape, at least in the outer half of the conveying tine or even in the outer two-thirds of the conveying tine.

[0022] The trailing edge of the conveyor tine, i.e., the trailing edge in the direction of rotation, can be concave overall. In particular, the trailing edge can have a region of increased concave curvature in the outer half of the conveyor tine, from which the trailing edge profile can flatten towards the tine end. That is, from this region of increased concave curvature, the concave curvature can become progressively larger outwards and may even reach indefinite, so that the trailing edge can have a straight profile in an outer tine area before transitioning into the flattened head area.

[0023] The aforementioned area of ​​increased concave curvature leads to a widening of the conveying tine at the trailing edge, or a broadened back profile. This prevents the conveying tine from shortening due to wear at the leading edge. At the same time, the leading edge can be optimally adapted to the desired conveying effect, in particular by adopting the previously described saber-shaped curvature.

[0024] In particular, the trailing edge of the conveyor tine may be concave when considering the outer half or even the outer two-thirds of the tine, so that a gap appears when a straight line is drawn along this trailing edge. The trailing edge may also have straight sections.

[0025] Regardless of the curvature of the front and / or rear edges, it can be advantageous for the conveying tines to be inclined relative to the radial direction, and in particular, inclined opposite to the direction of rotation. This allows the tines to flex, so to speak, under the weight of the crop, even though they can, of course, be rigid or unyielding.

[0026] In particular, the conveying tines can be inclined at an increasingly steeper angle towards the projecting tine end by means of an overall curved and / or bent contour. Considering the longitudinal centerline of a conveying tine, which extends midway between the front and rear edges of the tine when viewed in the direction of the rotor's axis of rotation, the inclination of said longitudinal centerline relative to the radial direction can increase towards the projecting tine end, preferably increasing continuously from the root region of the conveying tine to the projecting tine end.

[0027] The invention is explained in more detail below with reference to a preferred embodiment and the accompanying drawings. The drawings show: Fig. 1: A perspective front view of the receiving device of a harvesting machine such as a forage wagon or baler with a rotaryally driven conveying rotor for conveying crop through a crop channel; Fig. 2: A side view of a conveying tine of the conveying rotor. Fig. 1 when considering the conveying tine in the direction of the rotor axis of rotation, which shows the widened head area of ​​the conveying tine, and Fig. 3: a comparative side view of a conveying tine that is not widened in the head area according to the prior art and its shortening that occurs with wear.

[0028] How Figure 1As shown, the harvesting machine 1 can have a conveying device 3 with a conveying rotor 4, which connects to a receiving device 5 for picking up harvested material from the ground and conveys the picked-up harvested material into a functional space of the harvesting machine 1, such as the storage space of a loading wagon or the bale forming chamber of a bale forming press.

[0029] The aforementioned receiving device 5 can, for example, have a rotating spiked roller 6 in the form of a pickup, which transfers the harvested material to the conveying rotor 7, which then conveys the harvested material through a conveying channel 4 into the aforementioned functional space. A cutting unit 2 can be associated with the conveying rotor 7, the blades of which can protrude into the aforementioned conveying channel 4.

[0030] How Figure 1As shown, the conveying rotor 7 can have a plurality of conveying tines 8, which can be arranged in several rows distributed around the circumference, interlocking with one another or having a helical arrangement around the rotor axis of rotation 9. The aforementioned rotor axis of rotation 9 can be oriented horizontally, for example, transversely to the direction of travel of the harvesting machine 1. A plurality of conveying tines 8 can be arranged side by side and spaced apart from one another across the width of the conveying rotor 7 or along the rotor axis of rotation 9, cf. Figure 1 .

[0031] How Figure 2 As shown, the conveying tine 8 can taper overall from a tine root area 10, which lies in the transition area to the rotor axis of rotation 9, to the projecting tine end 11 when the conveying tine 8 is viewed in the direction of the rotor axis of rotation 9.

[0032] Regardless of this, the conveying tine 8, when viewed in the aforementioned direction, can have an overall saber-shaped contour, whereby the leading edge 12 of the tine can be convex overall, at least in the outer half of the tine furthest from the rotor axis of rotation 9. In the tine root area 10, the leading edge 12 of the conveying tine 8 can also be concave to achieve a smooth transition to the rotor axis of rotation.

[0033] Regardless of the aforementioned saber-shaped contour, the conveying tine 8 can be inclined to the radial direction 13 opposite to the direction of rotation 14, whereby the angle of inclination α can increase towards the free tine end 11, cf. Figure 2 , especially when a longitudinal centerline 15 of the conveying tine is considered in the direction of the rotor rotation axis 9.

[0034] The trailing edge 16 of the conveying tine 8 can be concave overall when the conveying tine 8 is viewed from the direction of the axis of rotation 9. In particular, the trailing edge 16 can have a region 17 of more pronounced concave curvature in an outer half of the conveying tine 8, from which the course of the trailing edge 16 flattens out towards the free end 11 of the tine. Overall, the trailing edge 16 is contoured such that the head region of the conveying tine 8 is widened.

[0035] How Figure 2 As shown, the conveying tine 8 has a blunt tine head at its free, projecting tine end 11 with a circumferential flattening 18 which extends tangentially to the circumferential direction of the conveying rotor.

[0036] The aforementioned flattening 18 forms a flat plateau surface. The aforementioned flattening 18 may be rounded towards the front and rear edges 12, 16, cf. Figure 2 .

[0037] When viewed in the direction of the rotor axis of rotation 9, the free tine end 11 has a width X in the area of ​​the flattening 18, where the said width X means the extent between the tine front edge 12 and the tine rear edge 16 in the area of ​​the flattening 18 and can be determined parallel to the circumferential direction and / or tangential to the flattening 18.

[0038] The aforementioned back widening, meaning the rear edge 16 being pulled further back against the direction of rotation, and the associated widening of the tine head, can prevent or reduce the shortening of the conveying tine 8 due to wear starting at the front edge. In comparison, consider a less or non-widened tine head, such as the one described above. Figure 3 As shown, the tine wear starting at the front edge 12 leads to a significant shortening of the conveying tine 8, as shown by the dashed wear line 19.

[0039] In comparison, corresponding wear on the conveying tine 8 with a widened tine head, as seen in the Figure 2 This shows that there is no significant shortening of the conveying tine 8, since the conveying tine 8 extends at its free tine end 11 approximately parallel to the direction of rotation due to the flattening 18. Although wear also affects the front of the conveying tine 8, the flattening 18 does not shorten the conveying tine 8; instead, it merely results in a more pronounced rounding of the leading edge 12 or of the transition from the tine leading edge 12 to the flattening 18.

[0040] The in Figure 2 The width X of the conveying tine 8 shown in the area of ​​the free tine end 12 or in the area of ​​the flattening 18 is, according to the invention, 0.3 to 2 times the material thickness of the conveying tine 8. The material thickness is measured in the direction of the rotor axis of rotation (9) perpendicular to the plane of the drawing. Figure 3must be measured. In particular, the width X can be approximately in the range of 60% to 180% or 80% to 150% of the stated material thickness.

[0041] Additionally, the aforementioned width X of the tine head is also adapted to the gap Z between the free tine end 11 and the surrounding wall of the conveying channel 4, where the width X is in the range of 10% to 100% of the aforementioned gap Z. In particular, the width X can be approximately 0.3 to 0.7 times the gap Z.

[0042] The width X can advantageously be 3 mm to 30 mm. In a further advantageous embodiment of the invention, the aforementioned width X can be 8 mm to 25 mm or 10 mm to 20 mm.

Claims

1. Harvester comprising a conveyor channel (4) for conveying harvested crop and a conveyor rotor (7) associated with the conveyor channel (4) having conveyor tines (8) for conveying the harvested crop through a cutting mechanism (2), wherein the conveyor channel (4) comprises a rotor housing wall surrounding the conveyor rotor (7), and wherein cutting blades (2) of the cutting mechanism project into the conveyor channel (4), along which the conveyor tines (8) of the rotating conveyor rotor (7) pass in order to cut the harvested crop, wherein the conveyor tines (8) project radially outward from a rotor rotational axis (9) and taper, when viewed in the direction of the rotor rotational axis (9), from a tine root section (10) toward a projecting tine tip (11) that forms a blunt tine head with a circumferential flattening (18), characterized in that the flattening (18) extends in the circumferential direction, and a width (X) of the tine tip measured in the circumferential direction, in the region of the flattening (18), when viewing the conveyor tine (8) in the direction of the rotor rotational axis (9), is within a range of 30 % to 200 % of the material thickness of the conveyor tine (8) measured in the direction of the rotor rotational axis (9) and within a range of 10 % to 100 % of a clearance (Z) between the projecting tine tip (11) and the rotor housing wall (20) surrounding the conveyor rotor.

2. Harvester according to the preceding claim, wherein the width (X) of the projecting tine tip (11) in the region of the flattening (18) is within a range of 60 % to 180 %, or within a range of 80 % to 150 %, of the material thickness of the conveyor tine (8).

3. Harvester according to any one of the preceding claims, wherein the width (X) of the projecting tine tip (11) in the region of the flattening (18) is from 3 mm to 30 mm.

4. Harvester according to the preceding claim, wherein the width (X) is from 8 mm to 25 mm or from 10 mm to 20 mm.

5. Harvester according to any one of the preceding claims, wherein the conveyor tines (8), when viewed in the direction of the rotor rotational axis (9), have a curved, sabre-shaped contour with an arcuate leading edge (12), the leading edge (12) preferably being continuously curved in an arcuate manner at least in the outer third of the conveyor tine (8) up to the flattening (18).

6. Harvester according to any one of the preceding claims, wherein a rear edge (16) of the conveyor tines (8) is overall formed in a concave shape when viewed in the direction of the rotor rotational axis (9).

7. Harvester according to the preceding claim, wherein the rear edge (16) has, in an outer half of the conveyor tine (8), a region (17) of intensified concave curvature, from which the course of the rear edge (16) flattens toward the projecting tine tip (11).

8. Harvester according to any one of the preceding claims, wherein the conveyor tines (8) are inclined with respect to the radial direction (13) counter to the direction of rotation (14), the inclination (α) of the longitudinal center line (15) of the conveyor tines (8) increasing toward the projecting tine tip (11), in particular continuously increasing from the tine root section (10) to the projecting tine tip (11).

9. Harvester according to any one of the preceding claims, wherein the conveyor rotor (7) is connected to a pickup device (5) for picking up the harvested crop from the ground and / or is arranged downstream of the pickup device (5).

10. Harvester according to any one of the preceding claims, wherein the conveyor channel (4), through which the conveyor rotor (7) conveys the harvested crop, leads to a functional space selected from the group consisting of a loading-wagon storage chamber and a bale-forming chamber.