Handheld scarifier

Abstract

Handheld scarifier (100), especially for soil preparation of lawns with a motor, in particular an electric motor (102), characterized by the fact that the scarifying device does not have any spacer devices, in particular wheels, and the scarifying device comprises a scarifying device, in particular a scarifying roller (1), which has at least one cutting disc (3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8) with two teeth (5.1, 7.1, 7.2, 7.3, 5.4, 5.5, 5.6, 7.7, 7.8) each, wherein the two teeth (5.1, 7.1, 7.2, 7.3, 5.4, 5.5, 5.6, 7.7, 7.8) are arranged opposite each other.

Description

[0001] The invention relates to a handheld scarifying device, in particular for soil cultivation, preferably lawn cultivation, in particular lawn aeration, with a motor, in particular an electric motor.

[0002] A variety of scarifying machines are known from the state of the art. Scarifying machines are generally used for lawn care, where they cut into the soil. This cutting promotes plant growth, as water, minerals, and fertilizer can reach the grass roots more easily. To maintain a constant distance from the lawn surface, two-axle scarifiers, as described in EP0485916A1, are used. The scarifying machine described in EP0485916A1 is a push scarifier.

[0003] Instead of the two-axle device described in EP0485916A1, single-axle push scarifiers are also known, for example, in EP0102604A2, which can be used for small areas. In the single-axle scarifier according to EP0102604A2, the scarifying roller is arranged on the same axle as the guide wheel. This is intended to ensure a uniform distance from the lawn surface in EP0102604A2. However, this is generally not the case, as the scarifying depth, which is usually 1 mm to 3 mm, can only be maintained if the lawn surface is level. This is rarely the case. Another problem is that edges that are difficult or impossible to access cannot be treated.

[0004] Furthermore, the scarifying result depends significantly on the geometry of the blades used. EP0260643A2 shows a scarifying machine with a blade shaft on which rotating scarifying blades are mounted at intervals along an axis.

[0005] The EP0472102A1 shows knives with teeth distributed around the circumference and special cutting edges.

[0006] German patent DE10 2010 044 301 A1 discloses a further embodiment of a single-axle garden scarifier in which the blades are cranked on both sides, allowing twice the number of grooves to be cut into the soil with a given number of blades. In the system described in DE10 2010 044 301 A1, the distance to the ground is also ensured by laterally mounted rollers. This device allows the height of the machine, and thus the cutting depth, to be adjusted within certain limits via an adjustment mechanism.

[0007] Another embodiment of blades in a scarifier is shown in EP2759186A1. The scarifier according to EP2759186A1 shows a blade assembly with a blade body, wherein a blade disc with four teeth is arranged at each end of the blade body and is used for scarifying.

[0008] All the previously described systems and scarifiers have in common that the distance to the ground, and thus the cutting depth, is adjusted by rotating wheels, either on a single or double axle. This makes working the lawn, especially on uneven terrain or at the edges, difficult.

[0009] The object of the invention is to provide a scarifying device that avoids the disadvantages of the prior art and, in particular, ensures good workability even in the case of uneven ground and in the edge areas of the lawn.

[0010] According to the invention, this problem is solved by providing a handheld scarifier, particularly for lawn preparation, equipped with a motor, especially an electric motor, wherein the scarifier is held solely by, for example, a handle, particularly a length-adjustable handle. The distance between the blades and the ground in a device according to the invention is ensured or determined by the shape of the blade disc. This means that the handheld scarifier according to the invention has no rollers or wheels to maintain the distance to the ground; this is ensured solely by the size of the blade disc.To intervene in the lawn area, the hand-operated scarifying device according to the invention comprises a scarifying device in the form of a scarifying roller, wherein the scarifying roller has at least one cutting disc with at least two teeth, wherein the least two teeth are arranged opposite each other.

[0011] In a further development of the invention, the scarifying roller of the scarifying device or scarifying machine has an axis and several cutting discs are arranged along this axis. An equidistant arrangement of the individual cutting discs of the scarifying shaft or scarifying roller relative to each other is preferred.

[0012] It is particularly preferred if knife discs or scarifying discs are arranged such that teeth are offset at an angle of 0 to 180°, in particular 45 to 90°, and in particular 60°.

[0013] The roller width of the scarifying roller is preferably between 100 mm and 500 mm, particularly between 150 mm and 180 mm. The scarifying roller itself is fitted with 6 to 20, preferably 6 to 10, blade discs. It has been found that a preferred spacing of the scarifying grooves is 1.5 cm to 2.5 cm. This spacing is preferred because it allows for the removal of moss and thatch while also ensuring the supply of minerals to the soil. To prevent damage to lawn roots, the inventors surprisingly discovered that the average distance between the individual blade discs with at least two teeth is in the range of 10 mm to 50 mm, preferably 15 mm to 30 mm, and particularly around 20 mm. If the distance between the blade discs with teeth is too narrow, for example less than 10 mm, not enough grass remains for effective scarifying.If, on the other hand, the spacing is too wide, i.e., wider than 30 mm, and especially wider than 50 mm, water penetration into the root system is insufficient for effective scarifying. Furthermore, with excessively wide spacing, not enough thatch is removed. Therefore, a spacing of 10 mm to 50 mm, and particularly 15 mm to 30 mm, between the blade discs is preferred. The overall width of the roller with blade discs is between 100 mm and 500 mm, preferably between 150 mm and 180 mm, and particularly 165 mm. Preferably, a total of eight blade discs are used at a width of 165 mm, resulting in a spacing of approximately 20 mm between each disc. A further advantage of using eight discs at a width of 165 mm is that the necessary distance to the ground can be maintained.

[0014] Since, when using disc blades as opposed to blades, the scarifying material kicked up during the process becomes trapped between the discs and the housing, this leads to the scarifying roller becoming blocked after only a short time, especially on damp soil. To prevent this, it is advantageous to provide a drive mechanism on the outer discs of the scarifying roller, with the drive mechanism arranged orthogonally to the outer disc. This design, with drive mechanisms on the two outer discs, the first disc, and the second disc of the scarifying roller, ensures that the scarifying material cannot become trapped between the disc and the housing. The drive mechanisms, arranged orthogonally to the outer discs, thus act as a kind of pinch protection.It is particularly preferred if the cutting edges on the blade discs are arranged at an angle ≥ 90° to the tangent of the disc in the area of ​​the blade. If the geometry of the blade disc were such that the cutting edge were arranged at an angle ≤ 90° to the tangent of the disc, this would have the disadvantage that dense root systems in the ground, as well as larger stones, could lead to increased stress on the drive train and thus to the blade disc becoming jammed. To counteract such extreme stresses, it is preferred if the cutting edge is flattened so that the cutting edge of the blade disc can slide over stubborn roots, stones, and other objects in the lawn. In particular, this also prevents stones from being dislodged from the ground, which could injure the operator.

[0015] The cutting edge is particularly preferably flattened at an angle α of 90° to 100° relative to the tangent in the cutting direction. This ensures that a blockage of the drive system is avoided. Furthermore, with this design, the load on the drive system is significantly reduced. Particularly good scarifying results are achieved at an angle of approximately 120°. At an angle of approximately 120°, only a low impulse load is exerted on the cutting disc and thus on the drive train.

[0016] It is particularly preferred if the cutting edges have a length in the range between 3 mm and 20 mm, in particular between 6 mm and 10 mm, and in particular between 8 mm.

[0017] The diameters of the toothed discs are preferably between 70 mm and 200 mm, particularly between 80 mm and 100 mm. Stainless steel, coated steel, or spring steel have proven particularly suitable materials for the cutting discs and teeth. The thickness of the cutting disc is between 0.5 mm and 1.5 mm, particularly between 0.9 mm and 1.1 mm. Preferably, a hexagonal profile is applied to the axle that supports the cutting discs, on which the individual cutting discs are arranged with spacers. The spacers preferably have an outer diameter between 20 mm and 90 mm, particularly between 30 mm and 40 mm. The optimal width of the spacers is 15 mm to 25 mm, particularly between 18 mm and 22 mm.

[0018] It is particularly preferred if the hand-held scarifier is guided by means of a handle, the handle preferably being rigidly connected to the motor housing and thus to the scarifying roller.

[0019] In contrast to wheel-guided scarifiers as shown in the prior art, the device according to the invention allows the operator to control the penetration depth. Thus, by applying appropriate pressure, the optimal penetration depth of 1 mm to 3 mm into the lawn can always be achieved. Since this distance cannot always be maintained with wheel-guided systems due to uneven ground, leading to unsatisfactory scarifying results, the hand-guided system ensures an optimal penetration depth and a uniform scarifying result. In particular, it is possible to compensate for larger irregularities in the ground, which is not possible with wheel-guided systems according to the prior art.

[0020] The invention will be described below with reference to exemplary embodiments.

[0021] They show: Fig. 1: An oblique view of a scarifying roller according to the invention with 8 knife discs arranged next to each other. Fig. 2: Overall view of a scarifying device according to the invention with a scarifying roller. Fig. 3: View of the scarifying machine in the area of ​​the scarifying roller. Fig. 4: Knife disc with at least two teeth, wherein the two teeth have a cutting edge with an angle α = 90°. Fig. 5: Knife disc with two teeth, wherein the knife disc has a cutting edge with an angle α = 120°.

[0022] Fig. Figure 1 shows a three-dimensional view of a scarifying roller 1 according to the invention, as used in the device according to the invention. The scarifying roller 1 comprises a total of 8 cutting discs 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8. Discs 3.1 and 3.8 are the two outer discs, which are arranged as shown in Figure 1. Fig. 3 shown with drive lugs 200.1, 200.2. Clearly in Fig. 1. The two teeth 5.1, 7.1, 7.2, 7.3, 5.4, 5.5, 5.6, 7.7, 7.8, which are arranged on one of the eight knife discs, can be seen.

[0023] The individual teeth 7.1, 7.2 of adjacent knives with cutting edges of the knife disc are preferably arranged offset by at least 60°.

[0024] The arrangement of the cutting edges or cutting teeth of the individual knife discs at an angle α > 90° or 120° to the tangent T to the knife disc is also clearly visible, as is the hexagonal profile 9 with which the individual knife discs can be mounted on an axis A, which runs perpendicular to the individual knife discs, using a spacer sleeve.

[0025] Fig. Figure 2 shows the complete, in particular handheld, scarifying device 100. The scarifying device 100 has a scarifying roller 1 which is driven by an electric motor 102 arranged above the scarifying roller in a housing 104. How Fig. As shown in Figure 2, the scarifying roller 1 is arranged centrally with respect to the handle 106. The axis A along which the scarifying roller is arranged is parallel to the motor axis. This allows for higher pressure forces to be applied. The scarifying roller is driven by a belt drive 110, which acts on the axis A of the scarifying roller or the scarifying shaft located there. Specifically, the belt drive can be, for example, a toothed belt. Compared to a gearbox, the toothed belt has the advantage that noise and vibrations from the roller are dampened and transmitted to the motor. The handle 106 includes a handle 112, which can also be removable for better control of the scarifier. In the illustrated embodiment, the handle itself has a plug 114, which serves as the power connection. An on / off switch is located on the handle to turn the scarifier off.A cable running inside the handle leads from the mains connection 114 located on the handle to the electric motor located in the motor housing. Instead of the mains connection shown, a battery, e.g., for 12 V, 18 V, 24 V or 36 V mains voltage, can also be provided, preferably a lithium-ion battery. In addition to the handle 112, an additional grip 116 is arranged on the handle for stabilizing the scarifier.

[0026] Fig. Figure 3 shows the lower section of the scarifier with the scarifying roller 1. Not shown is the electric motor, which drives a shaft 120 connected to a belt drive, preferably a toothed belt drive 110. The power of the electric motor (not shown) is transmitted via the toothed belt drive 110 to the axle 8 of the scarifying roller, thus driving the scarifying roller itself.

[0027] The scarifying roller, for example, comprises a total of 8 cutting discs as shown in... Fig. 1 shown and with the same reference numbers as in Fig. 1 is designated. Easily recognizable in Fig. The carriers 200.1 and 200.2, located adjacent to the outer discs 3.1 and 3.8 respectively, are positioned on the outer surfaces of the discs 3.1 and 3.8. The carriers 200.1 and 200.2 ensure that the scarifying material, which is stirred up between the scarifying discs and cannot become lodged in the housing, is transported away. This prevents the stirred-up scarifying material from becoming trapped between the individual blade discs 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, and 3.7. The individual discs are mounted on the shaft extending along axis A by means of spacers (not shown). The axis A, or the shaft running along the axis A, preferably has a hexagonal profile.

[0028] The Fig. 4 and Fig. Figure 5 shows in detail individual discs with knives and the angles of the cutting surfaces.

[0029] In Fig. 4 and Fig. The discs are labeled 3.1. The teeth are numbered 5.1 and 7.1.

[0030] The cutting disc with teeth 5.1, 7.1 includes a six-axis opening 300.1 in the center, into which the spacers, which are mounted along the shaft of the scarifying shaft, are inserted. The cutting edge 400.1 is also clearly visible, which in the design according to Fig. 4 has an angle α of 90° opposite the tangent T to the cutter disc.

[0031] A better result when scarifying is achieved with the design according to Fig. 5 is reached when the angle of the cutting edge to the tangent T is 120°. The disc according to Fig.5 with an angle of 120° shows a good scarifying result with low impulse load on the cutting disc and thus the drive train.

[0032] The invention provides, for the first time, a scarifying device that offers better scarifying results compared to wheel-guided scarifying devices.

[0033] The invention is particularly suitable for smaller, hard-to-reach lawns. Its handling is comparable to that of a rake, as the device is pulled towards the user during operation.

[0034] With a modular system, other attachments can be used instead of the scarifying roller. For example, in a cleaning and maintenance device, such as those described in DE 10 2014 010 692 A1 or US 2018 / 0 146 773 A1, it is particularly advantageous to simply replace the roller brush with the scarifying roller. This eliminates the need for a completely new device; the handheld scarifier can be used simply by swapping the roller brush for the scarifying roller. Thus, the cleaning and maintenance device disclosed in DE 10 2014 010 692 A1, for instance, can be used as a universal device for lawns and cultivated areas thanks to the easy interchangeability of the roller or brush. A scarifying roller requires relatively little storage space. This is particularly beneficial for smaller gardens, especially since scarifying is only necessary twice a year.Another advantage is that the scarifying roller can be used with various soil cultivation tools. These include corded, mains-powered soil cultivation tools as well as cordless, battery-operated ones.

Claims

[1] Handheld scarifier (100), especially for soil preparation of lawns with a motor, in particular an electric motor (102), characterized by , that the scarifying device does not have any spacer devices, in particular wheels, and the scarifying device comprises a scarifying device, in particular a scarifying roller (1), which has at least one cutting disc (3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8) with two teeth (5.1, 7.1, 7.2, 7.3, 5.4, 5.5, 5.6, 7.7, 7.8) each, wherein the two teeth (5.1, 7.1, 7.2, 7.3, 5.4, 5.5, 5.6, 7.7, 7.8) are arranged opposite each other. [2] Handheld scarifier according to claim 1, characterized by , that the motor, in particular the electric motor (102), acts on an axle (A) of the scarifying roller and drives it. [3] Handheld scarifier according to one of claims 1 to 2, characterized bythat the handheld device has at least one handle (106), in particular a handle (106) that is adjustable in length, and that the handle (106) is connected to a motor housing (104) of the motor, in particular an electric motor (102). [4] Handheld scarifier according to one of claims 1 to 3, characterized by that the teeth of the scarifying roller act directly on the lawn area to be treated and the penetration depth is preferably 1 mm to 3 mm due to the pressure of the operator. [5] Handheld scarifier according to any one of claims 1 to 4, characterized by , that on the axis A of the scarifying roller several knife discs (3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8) are arranged along the axis A preferably with a distance in the range of 10 mm to 50 mm, preferably 15 mm to 30 mm, to each other. [6] Handheld scarifier according to at least one of claims 1 to 5, characterized by, that the knife discs (3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8) are arranged equidistantly to each other. [7] Handheld scarifier according to any one of claims 1 to 6, characterized by , that adjacent cutter discs (3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8) are arranged such that the teeth (5.1, 7.1, 7.2, 7.3, 5.4, 5.5, 5.6, 7.7, 7.8) are offset by an angle between 0 and 180°, preferably 45 and 90°. [8] Handheld scarifier according to any one of claims 1 to 7, characterized by , that the scarifying roller (1) has a scarifying roller width, preferably in the range of 100 mm to 500 mm, in particular 150 mm to 200 mm, in particular 165 mm. [9] Handheld scarifier according to at least one of claims 1 to 8, characterized by , that the scarifying device includes in particular the scarifying roller (1) 6 to 20, in particular 6 to 10 knife discs (3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8). [10] Handheld scarifier according to at least one of claims 1 to 9, characterized by , that the scarifying roller comprises two outer knife discs (3.1, 3.8), a first outer knife disc (3.1) and a second outer knife disc (3.8) and the first and / or the second outer knife disc has at least one drive device (200.1, 200.2), wherein the drive device (200.1, 200.2) is arranged orthogonally to the first outer knife disc (3.1) and / or second outer knife disc (3.8). [11] Handheld scarifier according to at least one of claims 1 to 10, characterized by , that the teeth (5.1, 7.1, 7.2, 7.3, 5.4, 5.5, 5.6, 7.7, 7.8) of the cutter disc comprise a cutting edge S, wherein the cutting edge S has an angle α>90° relative to a tangent T to the cutter disc, particularly in the range of 90 to 140° relative to the tangent to the cutter disc. [12] Handheld scarifier according to at least one of claims 1 to 11, characterized by that the cutting edges have a length in the range between 3 mm and 20 mm, in particular 6 mm and 10 mm and / or the discs have a diameter between 70 mm and 200 mm, preferably 80 mm and 100 mm, and / or a thickness in the range of 0.5 mm to 1.5 mm, preferably 0.9 mm to 1.1 mm. [13] Handheld scarifier according to any one of claims 1 to 12, characterized by that the knife discs are made of stainless steel, coated steel or spring steel. [14] Handheld scarifier according to at least one of claims 1 to 13, characterized by , that at least one hexagonal profile is applied to the axis, on which the cutter discs are arranged with a spacer sleeve, wherein the spacer sleeve preferably has an outer diameter between 20 mm and 90 mm, in particular 30 mm and 40 mm.

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