Cutting device and method for cutting off plant material to be cut

Abstract

The invention relates to a cutting device (10) for cutting off plant material to be cut, such as hedges, branches and trunks, comprising a chassis (16) for attaching to a drivable carrier machine (14), more particularly to an excavator, and a cutting disk (20), which is driven rotationally about an axis of rotation (28) by a rotary drive (26) and which is provided with a plurality of cutting edges (30, 32) effective in at least one direction of rotation. According to the invention, the cutting disk (20) is rotatably mounted on a concentric counter-holder disk (22), and the counter-holder disk (22) has, on its circumferential edge, a plurality of counter-holder tongues (38), over which the cutting edges (30, 32) sweep and which are bounded by radially outwardly open insertion recesses (40) for the insertion of the material to be cut.

Description

[0001] Cutting device and method for separating plant cuttings

[0002] Description

[0003] The invention relates to a cutting device for cutting plant clippings such as hedges, branches, and trunks, comprising a chassis for attachment to a mobile carrier machine, in particular an excavator, and a cutting disc driven by a rotary drive to rotate about a rotational axis, which is provided with a plurality of cutting edges acting in at least one direction of rotation. The invention further relates to a method for using such a cutting device.

[0004] During maintenance work, for example, along roads or in open areas, various plants need to be trimmed back from time to time. This involves plant material of varying thickness, such as grass, hedges, thin branches, and even young trees with larger diameters, for example, up to 20 cm. Both hanging and standing grass should be trimmed back with a clean cut.

[0005] The disadvantage of using long shears with counter-blades is that the material being cut, such as branches, bends from the cutting edge to the counter-blade. This means that branches that are "too thin" are not cut crosswise but are sometimes slit lengthwise or break open. This in turn leads to branches being slit right down to the trunk, which causes tree disease. Another problem is that the carrier machine can only carry a limited weight, thus eliminating the need for heavy mechanical equipment. Various systems for cutting open the plant clearance profile using devices attached to excavators or similar machines (e.g. harvesters) are known in practice. These differ essentially in whether a continuous or discontinuous work process is possible.The continuously operating attachments, for example, use constantly running large circular saw blades arranged several times one behind the other.

[0006] Such a sawing device is also known from EP 3653042 A1. While fast-rotating saw blades produce a good cut, they are only effective on hanging material such as branches. When cutting upright material (trees), especially with larger diameters, these saw blades tend to jam quickly. When cutting thinner, very elastic material (such as hedges), the cut is unsatisfactory.

[0007] In addition, when used horizontally close to the ground, there is a constant risk of foreign objects (e.g. stones, waste, etc.).

[0008] Based on this, the invention is based on the object of further improving the devices and methods known in the prior art and of achieving the separation of different diameters and orientations of the cutting material with a clean cutting pattern with little handling effort.

[0009] To solve this problem, the combination of features specified in patent claims 1 and 17 is proposed. Advantageous embodiments and further developments of the invention emerge from the dependent claims.

[0010] The invention is based on the idea of ​​enabling the material to be cut to be fixed in place during the cutting process using continuously operating cutting means. Accordingly, the invention proposes that the rotatingly driven cutting disc be mounted on a concentric counter-holder disc, and that the counter-holder disc has a plurality of counter-holder tongues on its peripheral edge, which are swept over by the cutting edges of the cutting disc and which are bordered by radially outwardly open insertion recesses for inserting the material to be cut. By receiving the material to be cut in the insertion recesses, a defined positioning is achieved, with the counter-holder tongues acting as a support during the cutting process and thus enabling a clean transverse cut. Furthermore, the continuous rotation can also make use of the inertia of the cutting disc when it impacts the material to be cut.The attachment to a carrier machine also allows for large-scale work in a simple and quick manner without any special manual effort.

[0011] Advantageously, at least some of the insertion recesses have different opening widths, so that correspondingly different thicknesses of cuttings can be supported without excessive lateral play. For this purpose, it is particularly advantageous if the insertion recesses have a U-, C-, or V-shaped edge contour, although combinations of these are also conceivable. A further improvement in application possibilities can be achieved by having the opening widths of the insertion recesses in the range of 1 to 30 cm. This allows for a suitable holder to be provided for the relevant branch thicknesses, guaranteeing an optimal cutting angle.

[0012] A further embodiment provides that the counter-holding tongues have right-angled cutting edges or wedge-shaped counter-cutting edges that interact with the cutting edges.

[0013] According to a particularly preferred embodiment, it is proposed that the rotary drive be switchable, so that the cutting disc can be driven in a first direction of rotation or in the opposite direction in a second direction of rotation. Advantageously, the cutting edges of the cutting disc are provided with a radially straight shearing edge in one direction of rotation for shearing or chopping off the cutting material, thus enabling a clean cut with smaller branch cross-sections.

[0014] To ensure that even thick wood can be cut through, it is advantageous if the blades in the opposite direction of rotation are designed with a radially stepped saw edge for cutting off the cut material. It is particularly advantageous if the saw edge has 3 to 10 radially stepped steps.

[0015] For structural design, it is advantageous if the saw edge extends over the same radial length as the shear edge.

[0016] A further improvement results from the fact that the shearing edge and / or the sawing edge has a radial extension in the range between 10 and 20 cm.

[0017] In order to avoid blocking during the sawing movement, it is advantageous if the radially inner step of the saw edge is wider in the circumferential direction than the steps following it.

[0018] In order to keep the weight of the drive low and still be able to drive a sufficiently large cutting disc, it is advantageous if the rotary drive has a chain drive coupled to the cutting disc, preferably driven by a hydraulic motor.

[0019] To ensure the optimal orientation of the insertion recesses, it is advantageous if the counterholder disc is mounted so that it can be adjusted to a specific rotational orientation using a locking device, if necessary. To also make optimal use of moments of inertia for the cutting process, it is advantageous if the cutting disc's speed is between 10 and 80 rpm.

[0020] To avoid the risk of blockage, the rotary drive should be able to be switched off automatically when a torque limit is reached and optionally switched to the other direction of rotation.

[0021] Working close to the ground can be made easier by the chassis forming a skid that faces away from the cutting disc and can be placed on the ground to slide.

[0022] In order to be able to carry out repairs or adjustments easily if necessary, it is advantageous if the cutting disc and / or the counter-holder disc is composed of several segments fixed on a carrier.

[0023] A mechanical working process can be achieved by inserting the material to be cut into correspondingly oriented insertion recesses of the counterholder disc by a travel movement and / or manipulation of the carrier machine.

[0024] In terms of the method, to achieve the object mentioned above, it is proposed that a cutting device be mounted on a mobile carrier machine, and a cutting disc of the cutting device, provided with a plurality of cutting edges acting in at least one direction of rotation, be driven in a preferably continuous rotation about a rotational axis. The cutting disc is mounted concentrically on a counterholder disc, counterholder tongues on the peripheral edge of the counterholder disc are swept over by the cutting edges of the rotating cutting disc, and the material to be cut is introduced into insertion recesses in the counterholder disc, which are delimited by the counterholder tongues and open radially outwards. The advantages explained above with regard to a device are thus achieved in an analogous manner.

[0025] The invention is explained in more detail below using an exemplary embodiment schematically illustrated in the drawing. In the drawings:

[0026] Fig. 1 shows an excavator with a cutting device on the excavator arm in side view;

[0027] Fig. 2 the cutting device with a counter-holder disc and a segmented cutting disc in perspective view;

[0028] Fig. 3 and 4 the cutting device without and with cutting disc in side view; and

[0029] Fig. 5 is a section along line 5-5 of Fig. 4.

[0030] Fig. 1 shows a cutting device 10 on a stick or boom 12 of an excavator 14 as an example of a mobile carrier machine. The cutting device 10 is mounted on a chassis 16 by means of a quick-change device 18 at the end of the stick 12 and is pivotable and, if necessary, rotatable on a rotator using the kinematics of the stick 12. The cutting device 10 comprises a rotating cutting disc 20 and a counter-holder disc 22 for cutting off plant clippings, such as hard grasses, hedges, branches, and trunks, during a travel movement and / or manipulation by the excavator 14.

[0031] As can be seen from Figs. 2 and 4, the cutting disc 20 is composed of eight identical segments 24 and can be driven in rotation about the disc's central axis 28 as the axis of rotation by means of a rotary drive 26 arranged in the chassis 16. The rotary drive 26 is switchable so that the cutting disc 20 is driven in a first direction of rotation or in the opposite direction in a second direction of rotation.

[0032] Each segment 24 has two cutting edges 30, 32 on its outer edge, each of which has a cutting action in a direction of rotation of the cutting disc 20. A first cutting edge 30 is provided with a radially straight shearing edge 34 for shearing or squeezing the material to be cut, while the second cutting edge 32 is formed with a radially stepped sawing edge 36 for sawing off the material to be cut.

[0033] The sawing edge 36 expediently extends over the same radial length as the shearing edge 34, whereby, depending on the intended use, a radial extension in the range between 10 and 20 cm is advantageous.

[0034] In the example shown, the saw edge 36 has five steps, of which the radially inner step is wider in the circumferential direction than the steps adjoining it.

[0035] In the embodiment shown in Fig. 3, the counterholder disc 22 is formed in one piece and has a plurality of radially projecting counterholder tongues 38 on its peripheral edge, which are defined by radially outwardly open insertion recesses 40 for inserting the material to be cut. The U-shaped insertion recesses 40 have different opening widths, which can be determined as the respective arc length on an outer circle. The opening widths of the insertion recesses are expediently in the range of 1 to 30 cm.

[0036] In this way, a corresponding reception of cutting material of different thicknesses is possible, which is laterally supported on the counter-holder tongues 38 during the cutting process, while the cutting edges 30, 32 of the cutting disc 20 rotating concentrically on the counter-holder disc 22 sweep over the insertion recesses 40. To support the cutting process, it is also possible for the counter-holder tongues 38 to have rectangular cutting edges 42 or wedge-shaped counter-cutting edges that interact with the cutting edges 30, 32.

[0037] The counterholder disc 22 is mounted on the chassis 16, possibly for rotational adjustment, and is centered and guided at its central recess by a rotary head. This head is provided with screw holes 46 to which the segments 24 of the cutting disc 20 can be screwed. It is also possible for the axial distance of the cutting edges 30, 32 from the counterholder disc 22 to be adjustable by spacers 47.

[0038] As can be seen from Fig. 5, the chassis 16 comprises a motor housing 48 and a trough-like support structure 50 for the cutting disc 20 and counter-holder disc 22, projecting laterally therefrom. The support structure 50 forms, with its underside facing away from the discs 20, 22, a sliding skid 52 that can be placed on the ground so as to slide. For attachment to the excavator 14, a quick-change flange 54 is attached to the motor housing 48 opposite the support structure 50 and thus at a radial distance from the counter-holder disc 22.

[0039] The rotary drive 26 comprises a hydraulic motor 56 and a chain drive 58 for coupling the hydraulic motor 56 to the laterally spaced rotary head 44. By means of appropriate gear means 60, a speed of the cutting disc 20 can be conveniently selected in the range between 10 and 80 rpm.

[0040] To suitably position the insertion recesses 40 with their different opening widths, the counterholder disc 22 can be rotated into a desired rotational orientation and then locked securely to the device via locking means 62. This can be achieved by rolling the star-shaped protruding counterholder tongues 38 across the ground by a machine movement, temporarily overcoming the frictional engagement of the locking means 62, so that the excavator operator does not have to leave the driver's cab and does not have to perform any direct handling of the cutting device 10.

[0041] During operation, the arrangement of cutting and counter-holder slides 20, 22 can be guided horizontally, vertically or at an angle, whereby a movement relative to the material to be cut causes the material to be cut to enter the insertion recesses 40. During the work process, the material to be cut holds the counter-blade in position until the cutting process is completed. The cutting disk 20 rotates continuously so that inertial forces can also be used. To achieve a clean cut, the direction of rotation in which the linear shearing edges 34 are effective is initially selected. For very thick material to be cut, the rotary drive 26 can be provided to switch off automatically when a torque limit is reached and to be optionally switchable to the other direction of rotation, in which the steps of the sawing edges 36 then successively penetrate the material.

Claims

Patent claims 1. Cutting device for separating plant material such as hedges, branches and trunks, comprising a chassis (16) for mounting on a mobile carrier machine (14), in particular an excavator, and a cutting disc (20) driven by a rotary drive (26) about a rotary axis (28), the cutting disc being provided with several cutting edges (30, 32) acting in at least one direction of rotation, characterized in that the cutting disc (20) is rotatably mounted on a concentric counter-support disc (22), and that the counter-support disc (22) has several counter-support tongues (38) on its circumferential edge which are swept over by the cutting edges (30, 32) and which are bounded by radially outwardly open insertion recesses (40) for introducing the material being cut.

2. Cutting device according to claim 1, characterized in that at least some of the insertion recesses (40) which preferably have a U-, C- or V-shaped edge contour have different opening widths.

3. Cutting device according to claim 1 or 2, characterized in that the opening widths of the insertion recesses (40) are in the range of 1 to 30 cm.

4. Cutting device according to one of claims 1 to 3, characterized in that the counter-support tongues (38) have right-angled cutting edges or wedge-shaped counter-edges cooperating with the cutting edges (30, 32).

5. Cutting device according to one of claims 1 to 4, characterized in that the rotary drive (26) is switchable, so that the The cutting disc (20) is driven in a first direction of rotation or in the opposite direction in a second direction of rotation.

6. Cutting device according to one of claims 1 to 5, characterized in that the cutting edges (30, 32) of the cutting disc (20) are provided in one direction of rotation with a radially straight shearing edge (34) for shearing or squeezing off the material to be cut, and that the cutting edges (30, 32) are designed in the other direction of rotation with a radially stepped sawing edge (36) having preferably 3 to 10 steps for sawing off the material to be cut.

7. Cutting device according to claim 6, characterized in that the saw edge (36) extends over the same radial length as the shearing edge (34).

8. Cutting device according to claim 6 or 7, characterized in that the shearing edge (34) and / or the sawing edge (36) has a radial extension in the range between 10 and 20 cm.

9. Cutting device according to one of claims 6 to 8, characterized in that the radially inner step of the saw edge (36) is wider in the circumferential direction than the steps adjoining it.

10. Cutting device according to one of claims 1 to 9, characterized in that the rotary drive (26) has a chain drive (58) coupled to the cutting disc (20), preferably driven by means of a hydraulic motor (56).

11. Cutting device according to one of claims 1 to 10, characterized in that the counter-holder disc (22) is rotatably adjustable and can optionally be fixed in a specific rotational orientation by means of a locking device (62). Cutting device according to any one of claims 1 to 11, characterized in that the rotational speed of the cutting disc (20) is in the range between 10 and 80 rpm. Cutting device according to any one of claims 1 to 12, characterized in that the rotary drive (26) can be automatically switched off when a torque limit is reached and can optionally be switched to the other direction of rotation. Cutting device according to any one of claims 1 to 13, characterized in that the chassis (16) forms a sliding skid (52) facing away from the cutting disc (20) and which can be placed on the floor in a sliding manner. Cutting device according to any one of claims 1 to 14, characterized in that the cutting disc (20) and / or the counter-holder disc (22) is composed of several segments (24) fixed on a carrier.Cutting device according to claims 1 to 15, characterized in that the material to be cut can be inserted into appropriately oriented insertion recesses (40) of the counter-holder disc (22) by a travel movement and / or manipulation of the carrier machine (14). Method for separating plant material such as hedges, branches and trunks, in which a cutting device (10) is attached to a mobile carrier machine (14), and a cutting disc (20) of the cutting device (10) provided with several cutting edges (30, 32) acting in at least one direction of rotation is driven to rotate about a rotary axis (28), characterized in that the cutting disc (20) is mounted concentrically on a counter-holder disc (22), wherein counter-holder tongues (38) are located on the circumferential edge of the counter-holder disc. The counter-holder disc (22) is swept over by the cutting edges (30,32) of the rotating cutting disc (20), and the material to be cut is inserted into radially outwardly open insertion recesses (40) of the counter-holder disc (22) which are bounded by the counter-holder tongues (38).

Images