SINGLENESS

Abstract

To simplify the manufacture and improve a flail unit for shredding plant material, in particular green matter and / or small wood, the invention proposes a flail unit, in particular for a mulcher, with a flail holder with a retaining rod and with a flail with an opening in a flail head encompassing the retaining rod, in which at least one transverse dimension of the opening is larger than the transverse dimensions of the retaining rod.

Description

[0001] The invention relates to a flail unit, in particular for a mulcher, comprising a flail holder, a retaining rod and a flail with an opening in a flail head encompassing the retaining rod.

[0002] Flail units are known with a flail holder rigidly fixed to the rotor of a mulcher, in which the flails can only move around one axis of the flail holder. To give the flails greater mobility, flail units are already being developed in which a shackle is provided between the flail holder and the flail itself, allowing the flail a certain degree of freedom of movement, such as lateral swinging or evasive action. Further disadvantages of known flail units are that the flails have a solid shape, particularly a relatively large width along their entire height, which results in increased air resistance and limits the shredding effect. The weight distribution of the flail in known flail units is also such that it contributes to limiting its service life.

[0003] The invention is therefore based on the objective of creating a beater unit in which, without the intermediate arrangement of a shackle, the beater itself has greater freedom of movement, in particular degrees of freedom beyond pivoting about a holding axis.

[0004] According to the invention, the aforementioned problem is solved in a generic flail unit by ensuring that at least one transverse dimension of the opening is larger than the transverse dimensions of the retaining rod and / or that the retaining rod is cylindrical and that the cross-section of the opening is oval.

[0005] The transverse opening of the hammer can be designed as an elongated hole, in which case the transverse dimensions of the opening are constant along its entire length. Alternatively, the transverse dimensions of the opening can increase from its central section to the ends or openings, with the larger transverse dimension, in particular an oval cross-section, increasing towards the ends and openings of the hammer head. The smallest cross-sectional dimension can also increase, but preferably remains the diameter of the retaining rod – taking into account standard technical tolerances.

[0006] The design according to the invention ensures that the flail has greater mobility both in its extension direction or radial direction to the support rod and in the lateral direction along its transverse dimensions or in the extension direction of a rotor axis of the arrangement on a rotor.

[0007] This inventive design of a flail unit improves the shredding of plant material and allows flails to deflect when faced with excessively thick plant material, such as branches, thus increasing their service life.

[0008] In a further preferred embodiment, the larger cross-sectional dimension of the opening extends towards a cutting section of the hammer. This also applies accordingly to the cross-sectional dimension of the opening in the form of an elongated hole.

[0009] In a further development, the solution according to the invention provides that the largest transverse dimension of the opening is at least 1.2, preferably at least 1.4, times the largest transverse dimension of the retaining rod, wherein in particular the opening is an elongated hole and / or the retaining rod has a cylindrical cross-section.

[0010] In a further embodiment of the invention, the flail has a connection area from the flail head to a cutting section, which is narrower than the cutting section, wherein the width of the connection area is at most 0.3, preferably at most 0.25, of the width of the cutting section. This significant reduction in the width of the connection area considerably lowers the energy required to shred the plant material compared to known designs, since the narrowing of the connection area minimizes the ventilation effect caused by the movement of the flails and thus also improves the flow pattern – which is crucial for the material being shredded – by significantly reducing air stagnation and the formation of vortices behind the flails.

[0011] Furthermore, the aforementioned embodiment of the invention advantageously shifts the mass and center of gravity towards the outer edge of the flail, resulting in increased fatigue strength due to this outward shift of the center of gravity. Overall, this optimizes the cutting force and thus the cutting action of the flail.

[0012] The slimmer design of the flail in the connection area allows the material to flow more freely during the conveying process, slowing down as a result. This causes a larger portion of the biomass to be shredded to move outwards again due to the still-present centrifugal force. Subsequent flails then repeatedly grip the material radially from the outside, further shredding and fiberizing it through numerous flail contacts. This results in a further improvement in the quality of the mulched material in the final product.

[0013] In a preferred embodiment, an edge of the flail is provided that extends from the flail head at a finite angle other than 90°, preferably between 30° and 60°, and particularly between 40° and 50°, to approximately the middle of the flail, and / or that the flail head resting on the support rod has a width that is less than the distance to the radial limits restricting the axial movement of the flail along the support rod. This results in a peeling cleaning of the rod's surface, both during rotational movement of the flail around the support rod and during translational movement of the flail along the axis of the support rod. The rod thus remains free of deposits, making tool changes simple.

[0014] A preferred embodiment is characterized in that the flail has at least one rib on at least one side in a connection area, which extends perpendicular to the width of the cutting section, and in particular it is provided that the flail has ribs on both sides.

[0015] The reinforcing ribs ensure the necessary stability and fracture resistance despite the slimming of the connection area of ​​the flail, thus increasing the overall service life due to the larger material cross-section despite the reduction in the transverse dimensions of the connection area, especially in the actual cutting, crushing and conveying area on the outside.

[0016] While it is generally possible for the flail head to be wider than the connecting section, with the width of the flail head being at least twice the width of the connecting section, a preferred embodiment of the flail unit according to the invention is characterized by a tapered flail head, preferably having a width at most equal to that of the connecting section, and preferably the same width as the connecting section. In this embodiment of the flail, it is preferably provided that the flail holder is formed as a single block with a slot extending perpendicular to the support rod, into which the flail head engages. It is particularly provided that the slot widens towards the side of the block of the flail holder facing the flail, preferably widening in an arcuate convex shape, and in particular in a parabolic shape.

[0017] This further supports and improves the aforementioned improvements regarding the arrangement of gravity, distribution of mass of the flail and the resulting advantages in the working process, while maintaining the high mobility of the flail in the three degrees of freedom mentioned above (circumferentially around the support rod, radially and laterally).

[0018] Further advantages and features of the invention will become apparent from the claims and from the following description, in which exemplary embodiments of the invention are explained in detail with reference to the drawing.

[0019] This shows: Fig. 1 a perspective view of a mulcher rotor with flail units according to the invention arranged on it; Fig. 2 a front view of a first flail unit; Fig. 2.1 a front view of the flail unit of the Fig. 1 with a laterally pivoted mallet; Fig. 2.2 an enlarged perspective view of the embodiment of the mallet Fig. 2 ; Fig. 2.3 a side view of the mallet of the Fig. 2.2 with a cross-section through the support rod of the unit; Fig. 2.4 a sectional view corresponding to AA of the Fig. 2.3 of the first embodiment of the mallet according to the invention; Fig. 2.5 the arrangement of two mallets of the Fig. 2.2 in a double-flap unit; Fig. 3 a second embodiment of a flail according to the invention; Fig. 3.1 a side view of the second embodiment of the flail according to the invention Fig. 3 Fig. 4 shows a perspective view of a further embodiment of a beater unit according to the invention; Figs. 4.1, 4.2 show two radial positions of the beater in the beater unit of the Fig. 4 (referring to a rotor to which the flail unit is attached); and Figs. 4.3, 4.4 Front views of the flail units of the Fig. 4 in both positions of Fig. 4.1 und 4.2 .

[0020] Flail units according to the invention are used for shredding plant material, in particular green matter and / or small-diameter wood, preferably in a mulcher. The flail units 1 according to the invention are attached to a rotor 2 in a helical arrangement in the axial direction thereof, for example in two helixes, as is the case in the Fig. 1 The diagram shows that each helix extends approximately 1.5 turns in circumference.

[0021] A flail unit 1 essentially consists of a flail holder 3 with retaining cheeks 3.1 to be attached to or already attached to the rotor 2 and a retaining rod 3.2 or bearing bolt inserted through these, preferably in the form of a machine screw with a widened screw head 3.3, a fixed cylindrical holding area and a screw end applied to the screw head 3.3 as well as a nut 3.4 screwed onto the screw end, whereby the retaining rod 2.3 is held in the cheeks 3.1 and thus on the rotor 2.

[0022] The flail unit 1 further comprises a flail 4 which is pivotably mounted on the retaining rod 3.2. The flail 4 has a flail head 4.1 with an opening 4.2 or an elongated hole. The flail 4 is held on the retaining rod 3.2 by its opening 4.2 engaging with the retaining rod 3.2. The retaining rod 3.2 has a circular cross-section, as shown in particular in Fig. 2.3 as shown; it is therefore cylindrical. The opening 4.2 has an oval cross-section, the smallest transverse dimension of which—taking into account usual technical tolerances—corresponds to the diameter of the retaining rod 3.2, while the second transverse dimension perpendicular to this, in the direction of the cutting section 4.4 or cutter head, is increased beyond usual tolerances. In the illustrated embodiment, the opening is designed as an elongated hole in the direction of extension of the flail 4 and has a substantially oval cross-section with a larger extension in the direction of the flail and a smaller transverse dimension perpendicular to this, as is particularly evident in the Fig. 2.3 is recognizable.

[0023] The transverse dimension of the opening 4.2 in the extension direction of the hammer is approximately 1.4 times the width of the elongated hole perpendicular to it.

[0024] This design with a cylindrical support rod 3.2 allows the flail 4 to move radially relative to the rotor 2 relative to the flail holder 3, in addition to pivoting around the support rod 3.2, and also to tilt to a certain extent in the direction of the support rod 3.2, as shown in the Fig. 3.1 . is evident.

[0025] A connecting area 4.3 between flail head 4.1 and a cutting section 4.4 is tapered compared to the latter two, as is particularly evident from the Fig. 2.2 It can be seen that the transverse dimension of the connecting section 4.3 in the width direction of the cutting section 4.4 in the illustrated embodiment is less than 0.25 and also less than half the width of the flail head 4.1. To reinforce the connecting section 4.3, which has been reduced in width in this way, a rib 4.5 is provided on the front side.

[0026] The connection area 4.3 has an inclined plane or edge 4.3.1 extending from the flail head 4.1 to approximately the middle of the flail 4, with a finite angle of less than 90° to the axis of the support rod 3.2, preferably between 30° and 60°, here approximately 40°. This results in a peeling cleaning of the rod's surface both during rotational movement of the flail 4 around the support rod 3.2 and during translational movement of the flail 4 along the axis of the support rod. The rod thus remains free of deposits, making tool changes simple.

[0027] The Fig. 2.5 shows that two mallets 4 of the design of the Fig. 2.2 can be arranged directly next to each other in a double flail unit 2a and in particular retain their lateral pivotability as described above.

[0028] The Fig. 3 Figure 1 shows a second embodiment of a flail 4 according to the invention. This flail also has an elongated hole 4.2 in the flail head 4.1 for attachment to a retaining rod, as described above. The flail 4 again consists of a flail head 4.1, a connecting section 4.3, and a cutting section 4.4. The connecting section 4.3 is again tapered in width compared to both the cutting section 4.4 and the flail head 4.1 and has a rib 4.5 on its front side for reinforcement. The design of the Fig. 3 is designed for larger mallets. Therefore, the entire mallet is somewhat more robust than the mallet of the Fig. 2 ff., in particular also the connecting section 4.3, whose width is nevertheless less than 0.3 of the width of the cutting section 4.4.

[0029] The Fig. 4 Figures ff. show a further embodiment of a beater unit 1 according to the invention. The design of retaining rod 3.2 and opening 4.2 and their relationship correspond to the first embodiment, so that reference can be made to the above description, in particular the Fig. 3.1 is referred to. The design of the Fig. 4 The design does not have a flail holder with two separate cheeks, as is the case in the embodiments described above, but rather a flail holder 5 with a one-piece retaining block 5.1 on the cheeks 5.2 extending from its mounting surface to the rotor or from the rotor to the flail 4, with a slot 5.3 located between these cheeks and widening towards the flail 4. The cheeks 5.2 have openings through which the retaining rod, designed as a screw, is inserted in the usual manner and secured by means of a nut (not visible in the illustration). Fig. 4 ) is fastened by means of a hole, as is particularly evident with reference to Fig. 2.4 was described.

[0030] In this embodiment as well, the flail 4 has a connecting area 4.3 between the cutting section 4.4 and the flail head 4.1, which encompasses the retaining rod 3.2, that is tapered compared to the width of the cutting section 4.4 or has significantly smaller dimensions. Furthermore, the flail 4 tapers from the cutting section 4.4, via the connecting section 4.3, to the flail head 4.1, which can thus engage in the slot 5.3 of the holder 5.

[0031] The slot 5.3 of the holder 5 widens from its base towards its free opening with convex, in particular parabolic, walls in section, as can be clearly seen in particular in Fig. 4.6.

[0032] In this design as well, the mallet 4 again has a rib 4.5 extending from its connection area 4.3 to its mallet head 4.1, which necessitates a reinforcement of the mallet.

[0033] The hammer 4 of the design of the Fig. 4 The following degrees of freedom are available: First, the hammer can pivot around the retaining rod 3.2 in the usual, and indeed known, manner. Radial mobility relative to the axis of the rotor, or into and out of the slot 5.3, is also possible, as is the case in the Fig. 4.1, 4.2 as well as the Fig. 4.3, 4.4 This is recognizable. In addition, the hammer 4 can pivot in the direction of the support rod 3.2.

Claims

1. Flail unit, in particular for a mulcher, comprising a flail holder (3) with a retaining rod (3.2) and a flail (4) with an opening (4.2) encompassing the retaining rod (3.2) in a flail head (4.1), characterized by the fact that at least one transverse dimension of the opening (4.2) is larger than the transverse dimensions of the retaining rod (3.2).

2. Unit according to the preamble of claim 1, in particular according to claim 1, characterized by the fact that the retaining rod (3.2) is cylindrical and the cross-section of the opening (4.2) is oval.

3. Unit according to claim 2, characterized by the fact that the larger cross-sectional dimension of the opening (4.2) extends in the direction of a cutting section (4.4) of the hammer (4).

4. Unit according to one of claims 1 to 3, characterized by the fact that the largest transverse dimension of the opening (4.2) is at least 1.2, preferably at least 1.4, times the largest transverse dimension of the retaining rod (3.2).

5. Unit according to any one of claims 1 to 4, characterized by the fact that the breakthrough (4.2) is a slot.

6. Unit according to any of the preceding claims, characterized by the fact that the retaining rod (3.2) has a cylindrical cross-section.

7. Unit according to any of the preceding claims, characterized by the fact that the flail (4) has a central connecting area (4.3) from the flail head (4.1) to a cutting section (4.4) which has a smaller width than the cutting section (4.4), wherein in particular the width of the connecting area (4.3) is at most 0.3, preferably at most 0.25 of the width of the cutting section (4.4).

8. Unit according to any of the preceding claims, characterized by the fact that An edge (4.3.1) of the mallet (4) is provided, extending at a finite angle other than 90°, preferably between 30° and 60°, in particular between 40° and 50° from the mallet head (4.1) to approximately the middle of the mallet (4).

9. Unit according to any of the preceding claims, characterized by the fact that the flail head (4.1) resting on the support rod (3.2) has a width that is less than the distance from the radial limits (3.3, 3.4) limiting the axial movement of the flail (4) along the support rod (3.2).

10. Unit according to any of the preceding claims, characterized by the fact that the flail (4) has at least one rib (4.5) in a connection area (4.3) which extends perpendicularly to the width of the cutting section (4.4), wherein in particular the flail (4) has ribs (4.5) on both sides.

11. Unit according to any of the preceding claims, characterized by the fact that the flail head (4.1) is wider than the connecting area (4.3), in particular the width of the flail head (4.1) being at least twice the width of the connecting area (4.3).

12. Unit according to any one of claims 1 to 10, characterized by the fact thatthe flail head (4.1) is tapered.

13. Unit according to claim 12, characterized by the fact that the flail head (4.1) has at most the width of the connecting section (4.3), preferably the same width as the connecting section (4.3).

14. Unit according to claim 12 or 13, characterized by the fact that the flail holder (3) is designed as a one-piece block with a slot extending perpendicular to the support rod (3.2), into which the flail head (4.1) engages.

15. Unit according to claim 15, characterized by the fact that the slot widens towards the side of the block of the mallet holder (3) facing the mallet (4), in particular the slot (5.3) widens in an arc-shaped convex shape, in particular in a parabolic shape.