Cutting device, in particular mowing device, preferably lawn edge cutting device

Abstract

The invention relates to a cutting device, in particular a lawn cutting device, preferably a lawn edge cutting device, comprising at least one cutting device, which has a blade assembly comprising at least one lower blade and at least one upper blade, which can be moved relative to one another, preferably in a swinging manner, the at least one upper cutter is provided with at least one first upper cutter and at least one second upper cutter. The invention is characterized in that the cutting device has a drive unit for the first upper blade and the second upper blade, preferably in the form of an electric motor, and the drive unit is a common drive unit for at least the first upper blade and the second upper blade, and the drive unit comprises at least three gears, wherein the three gears comprise two gears of substantially the same size, in particular of substantially the same diameter, namely a first gear and a second gear each having an eccentric disk, and a third central gear is designed for meshing with the first gear and the second gear, the third central gear being connected to a pinion of the electric motor.

Description

Technical Field

[0001] The present invention relates to a cutting device, in particular to a grass cutting device, preferably to a lawn edge cutting device. Background Art

[0002] The cutting device according to the invention is a cutting apparatus, such as the cutting device is used, for example, for mowing grass. As trimming devices, cutting devices that work according to the shearing principle can be divided into pole mowers and lawn mowers according to the prior art.

[0003] A pole mower has a blade that oscillates in translation. In contrast, in a lawnmower the blade oscillates around a point of rotation.

[0004] For example, a rotary oscillating system as a lawn mower is shown in US 3623223 A. The system shown in US 3623223 A consists of a fixed lower knife and a rotary oscillating upper knife. Here, the upper knife is driven by an eccentric disk, which is preferably directly connected to an electric motor through a shaft.

[0005] Pole mowers are mainly used for larger cutting widths in agriculture. The pole mower disclosed by EP 2853142 A1 has a blade carrier guided on both sides. WO 1999 / 07202 A shows a hand-operated pole mower with a blade carrier designed on one side. The blade carriers of these pole mowers have a cutting width of about 500 mm to several meters.

[0006] Instead of a pole mower, a lawnmower can also be used for mowing. The advantage of a lawnmower is its simple structure and the resulting low power loss caused by the minimized friction effect. This plays a role in the longer operating time of battery-driven devices. However, the disadvantage of lawnmowers is that they are limited in cutting width and are only suitable for narrow grass strips, which cannot be grasped and therefore remain motionless when mowing the surface on the edge with a commercial lawnmower. The larger cutting width of a lawnmower can only be achieved by arranging a plurality of, for example, two lawnmower blades side by side, as shown in EP 1886551 A1. In EP 1886551 A1, there is no description for driving two (also called upper blades) lawnmower blades.

[0007] In recent years, lawn robots have established a strong application, especially in small gardens. Lawn robots are used to drive and autonomously cut the grass in a specified area according to a random or specific pattern. In edge areas, especially in front of walls or house facades, there are usually at least 200 mm strips of grass that cannot be cut. However, this type of edge strip is too wide for the use of lawn edge trimmers. Such areas can then be cut in multiple processes using only lawn shears.

[0008] US 3973378 shows a system with four rotating and swinging upper knives on a fixed lower knife, and the lower knife has enough width for cutting in the edge area of ​​the grass. This device is also particularly suitable for small areas. In US3973378, two knives are driven by a lever on both sides symmetrically about the central axis along the cutting direction. The corresponding lever on each side is driven by a crank arranged on the gear outside the gear axis and is placed in a translational swinging motion transverse to the working direction of the lawn mower. Due to the force transmission on the long holes of the two cranks and the long holes of the four knives, high power loss due to sliding friction occurs. In addition, the lever must also be guided in the long hole, thereby further improving the power loss. The power loss in the power supply device connected by the cable plays a secondary role, and the excessive power loss in the battery-driven device significantly shortens the running time. Summary of the invention

[0009] The object of the present invention is therefore to avoid the disadvantages of the prior art and in particular to provide a cutting device which is characterized in that it allows cutting of edge areas in front of walls or house facades using a battery with an energy of 45 watt-hours (Wh), in particular with a high battery operating time of approximately 1 hour. In addition, the cutting device with at least two upper knives should be designed so that the at least two upper knives can be driven in a pivoting manner, preferably in a simple manner. In particular, additional and additional control devices which synchronize the drive of the at least two upper knives should be avoided.

[0010] This object is achieved according to the invention by a cutting device according to claim 1 .

[0011] Developments of the invention are the subject matter of the dependent claims.

[0012] The cutting device according to claim 1 is characterized in that it is provided with a common drive unit for driving the plurality of upper knives, preferably for all upper knives, but at least for the first and second upper knives.

[0013] In a first embodiment of the invention, the cutting device comprises a transmission mechanism of preferably three gears as a common drive unit, wherein two gears are substantially the same size, and also comprises a first and a second gear each having an eccentric disk, which is driven by a third central gear, and the drive of the third central gear is carried out by a motor pinion. Compared with the prior art, such as US Pat. No. 3,973,378, this arrangement of gears and eccentrics in a directly driven component with an upper knife is significantly more efficient and frictionless. In contrast to the present invention, in US Pat. No. 3,973,378, a translationally oscillating lever is driven on each side by a drive gear with an eccentric, which causes the upper knife to rotate and oscillate through an elongated hole. This has significantly more movable components than in the present invention, which leads to greater friction losses relative to the drive assembly according to the present invention, which leads to a lower battery operating time and is therefore disadvantageous in battery-operated devices. The device according to the present invention is characterized in that the device comprises a maximum of three gears in a particularly frictionless type, and the first and second gears are driven by a central gear. Of course, types with more than three gears are also conceivable, but the friction losses will increase, which is undesirable.

[0014] Another advantage of the cutting device according to the invention having only three gears is its compact structure, which has a very low total weight of less than 2.5 kg, in this case 2.4 kg, without batteries. In addition, the device is very handy and easy to operate.

[0015] In a second embodiment of the invention, the cutting device comprises an upper knife, which is arranged on a preferably fixed lower knife, and the lower knife has at least one opening for conducting the cut grass.

[0016] Particularly preferably, in an embodiment of the cutting tool with two upper knives and a fixed lower knife, the opening, in particular the one opening, is arranged in the middle of the lower knife so that it is located in the middle between the two upper knives.

[0017] In a further improved embodiment, the cutting device comprises a cover in the form of a gear mechanism cover which protects the gear mechanism from the penetration of dirt.

[0018] It is particularly preferred that the lower knife is a fixed lower knife, on which at least the first and second upper knife are arranged via a rotation point. The upper knife fixed to the fixed lower knife performs a swiveling motion around the rotation point. This is achieved in that the first and / or second upper knife moves in a first and / or second eccentric guide insert with an eccentric disk around the first and / or second rotation point. It is particularly preferred that the upper knife moves in a rotationally swiveling manner in the first and / or second eccentric guide insert, preferably with the aid of an eccentric disk. In particular, the first and second upper knife move in opposite directions, since vibrations due to the rotationally swiveling motion can be reduced or even completely avoided.

[0019] In particular, when two upper knives moving in opposite directions are used, the amplitudes can be reduced and thus the vibrations can be significantly reduced compared to one oscillating knife and one fixed knife.

[0020] The advantage of the upper knife with rotational motion over the knife holder with translational motion is that they can be preloaded more easily and generate less friction. In addition, for example in the case of an ornamental lawn, a neat cutting of grass stems and / or grass blades can be achieved. Preferably, the first upper knife comprises a first drive gear or gear, and the second upper knife comprises a second drive gear or gear. In order to achieve a common drive of the first and second upper knives, it is provided that the cutting device comprises a central gear, which preferably acts on the first and second gears of the first and second upper knives. In this way, both the first upper knife and the second upper knife can be driven by a single motor, for example an electric motor, which acts on the central gear.

[0021] CN 207099687 U shows a structure with a fixed and two rotating and oscillating upper knives. The system of CN 207099687 U consists of two transmission mechanisms each having an eccentric gear, which is driven by a pinion on a drive gear shaft. The two parallel transmission stages are driven in the center by a motor pinion. Compared with the present invention with three gears and one motor pinion, six gears and one motor pinion are meshed in CN 207099687 U. Due to this structure with many components, friction losses are increased again, which is particularly disadvantageous in battery-driven devices.

[0022] In contrast, the present invention uses a smaller number of gears. This minimizes friction losses and increases the operating time. Specifically, in CN 207099687 U, a total of four gear pairs are in meshing, while in the present invention, only three gear pairs are in meshing. If the efficiency of the lubricated gear pair made of plastic is set to about 0.85, the power loss in CN 207099687 U is at least 15% compared to the present invention simply due to the design of the transmission mechanism. Minimizing losses is particularly meaningful in battery devices because it extends the operating time. According to the present invention, the design of the drive device can reduce losses to a minimum and increase the operating time of the battery used in the gardening tool.

[0023] US 6314707 also shows a cutting device, in particular for grass cutting, having a fixed lower knife and a cutting knife that swings on the fixed lower knife. The prior art in the form of US 6314707 has a transversely arranged knife holder with teeth, on which two upper knives are translated and swung transversely to the cutting direction. The two upper knives are driven via a crankshaft in the middle of the knife holder. The crankshaft is connected to the two upper knives with a connecting rod each. By arranging the crank on the crankshaft, the upper knives move in opposite directions to minimize vibrations. The pretensioning of the upper knives is achieved via a tensioning line. Since the upper knives in US 6314707 are flat on the fixed knife holder, the loss friction is significantly higher than the loss friction in the arrangement structure according to the invention.

[0024] The drive of the first and second upper knives is coordinated by a single electric motor, and a control device for driving the first and second gears is not necessary. If the eccentric discs in the eccentric insert are oriented in opposite directions, a common swinging movement of the first and second upper knives, which is directed in opposite directions to each other, is triggered. Due to this swinging reverse movement, vibration can be reduced. Preferably, the common gear is driven by a drive unit, especially an electric motor, wherein the electric motor preferably has a mechanical rated power in the range of 30 watts to 100 watts. This drive within the above power range is optimal for cutting grass stems or grass blades. In the case of driving with an electric motor by means of a central drive gear as described, an electric motor with significantly reduced power can be used. Expensive bevel gear transmission mechanisms are not required. A significantly smaller motor with coordinated power for a cutting device according to the present invention has the advantage that the motor and the cutting device can be manufactured significantly more easily and lead to weight reduction.

[0025] Furthermore, the arrangement does not have to be designed with a high motor power in order to prevent damage to components, for example, in the event that the first upper blade and / or the second upper blade gets stuck. As a result, the device can be easily assembled and is easy to handle in terms of operation. Without batteries for the cutting device, a weight of 2.0 kg to 3.0 kg, preferably 2.4 kg, can be achieved.

[0026] The problem of the upper knife vibrating in reverse motion is that after a short running time, the cut grass can be present between the two upper knives. If the two upper knives move toward each other from the outer cutting position, the corresponding blades will cut grass blades and grass stems on the corresponding cutting sides of the blade of the lower knife. On the other hand, the two upper knives are limited by the lower knife and by the cover to protect the transmission mechanism from the invasion of dirt and grass. In addition, a foam seal is provided in the region of the upper knife below the cover to close the air gap determined by the design between the upper knife and the cover. If the upper knife moves toward each other, the cut material is squeezed together in the gap between the blades. This process is carried out in each reciprocating motion and due to the continuous re-extrusion of the squeezed cut material, the foam seal that plays a shielding role cannot prevent the invasion of the cut material. Therefore, in a particularly preferred embodiment, an opening is provided, which is used to guide the cut material downwards. For this reason, the opening is preferably arranged in the center of the lower knife so that the opening is centrally located between the two upper knives and before the transmission mechanism seal in the lower knife. The cut material is then guided downward through the opening and thereby ensures that the transmission mechanism remains free of dirt.

[0027] In addition to a mechanical rated power of 30 W to 200 W, preferably 40 W to 100 W, it is particularly preferred that the drive unit used in the cutting device according to the invention has a current consumption or electrical power of 30 W to 200 W. The low current consumption due to low friction losses also leads to a very long operating time of the cutting device driven by a storage device, such as a battery, which in the case of a battery with 18 V, 2.5 Ah and 45 Wh of energy is 40 to 80 minutes, preferably 40 to 50 minutes.

[0028] Particularly preferably, the cutting device has a knife assembly comprising a lower knife and a plurality of upper knives, wherein a cutting width in the range of 100 mm to 400 mm is provided. The advantage of this cutting width is that even stranded grass strips can be cut by a single cut when using the lawn robot. A cutting width of 250 mm is very particularly preferred. This cutting width ensures that grass strips can be reliably cut and removed in the edge area. In addition, with this cutting width, small lawn surfaces can also be cut. Lawn mowers for small gardens or small devices usually start with a cutting width of at least 220 mm.

[0029] Not only the fixed lower knife but also the first upper knife and the second upper knife have narrow blades, wherein the elastic blades can be easily bent under load and therefore affect the cutting result. However, when the upper knife, i.e. the first and second upper knives are preloaded, the high elasticity disadvantages of the upper knife and the lower knife can be advantageously utilized. By preloading the upper knife, better cutting results can be achieved compared with the unpreloaded upper knife. As in shearing machines, in this case, the blade also always cuts on the contact surface between the upper knife and the lower knife. By preloading, the spacing between the blades directed to each other by the knives is getting smaller and smaller. The contact points of the cutting edges of the upper knife and the lower knife are then in a preloaded state. Preloading ensures that the cutting edge always keeps in contact during operation. If the preloading is insufficient or does not exist, then, for example, the cutting material such as the straw cannot be cut. Subsequently, the straw is bent, especially because the contact surface between the upper knife and the lower knife is not enough. In order to produce preloading, it is advantageously provided that a spacer is provided between the lower knife and the first upper knife or the second upper knife, so that preloading is applied or established.

[0030] By setting the pretension of the first upper knife and the second upper knife, the pretension applied to the first upper knife and the second upper knife becomes smaller and smaller in the direction of the blade. Despite the presence of the pretension, due to the elasticity of the blade, the friction and therefore the required motor power are reduced. The spacing between the upper knife and the lower knife caused by the spacer to be pretensioned is 1 to 4 mm, ideally 3 mm. By pretensioning, the two upper knives and the lower knife slide very closely to each other. By pretensioning, it is surprisingly achieved that the blades of the lower knife and the first and second upper knives are always superimposed on each other and in contact at the cutting surface, thereby ensuring neat cutting. In order to ensure sufficient spacing between the cutting knife and the grass surface, it is preferably provided that the cutting device includes at least two wheels, which are preferably arranged along an axis and can be adjusted in height.

[0031] In order to guide the cutting device according to the invention, it is preferably provided that a lever is arranged on the cutting device. The lever is preferably designed centrally relative to the cutting device or the cutting tool and is provided with a handle as well as a switch and a holder for a storage device, for example a battery. It is very preferred that the lever is not rigidly mounted on the cutting device, but by means of an articulation, preferably a fixed articulation, in particular a rotatable fixed articulation. By means of the fixed articulation, the lever can be brought into different positions, so that, for example, grass can also be cut with the lever in the flipped state under bushes or trees. Operation with an accumulator or battery, for example a lithium-ion battery, is advantageous because this avoids cables.

[0032] Particularly preferably, the drive unit for driving the first and second upper knives comprises an electric motor. The electric motor can be powered by a storage device or a battery. By vertically mounting, for example, a bevel gear transmission can be used to drive a central gear, which in turn acts on a first and a second gear, which are assigned to the first and second upper knives and drive the first and second upper knives in particular synchronously. The central gear and the first and second gears have a diameter and teeth. For the drive, it is advantageous that the electric motor acts on the central gear with a motor pinion or pinion, and the motor pinion or pinion has teeth. In this case, the transmission ratio can be set by selecting the diameter and number of teeth of the motor pinion or pinion and the central gear. Particularly preferably, the transmission ratio is set to a value of 1 to 10 based on the number of teeth of the pinion and the first gear or the second gear. Here, the total transmission ratio from the pinion to the eccentric mechanism is 1:10 and the total transmission ratio from the pinion to the central gear is 1:5.9. The values ​​of the transmission ratio given have been proven to be particularly advantageous and preferred values. Of course, other values ​​are also conceivable for those skilled in the art. Thus, the value of the transmission ratio from the pinion to the eccentric can be shifted, for example, within a range of 1:5 to 1:50.

[0033] The first and second upper blades can be driven by means of the first and second gearwheels in such a way that they are pivoted relative to one another.

[0034] Not only the lower knife but also the first upper knife and the second upper knife have a plurality of blades. In particular, preferably in the lower knife, the lower knife has a middle and a first and a second edge region, wherein the blades of the lower knife are aligned in the middle region. The blades of the first and second upper knives can also extend in the edge region.

[0035] The extension of the blade in the middle region of the lower blade results in a secure cutting of the grass during the movement of the upper blade, since the grass stems are guided, which then results in them being cut off by the blade of the upper blade in the rear region.

[0036] It can be particularly preferably provided that the cutting device has a separate base plate. The first and second upper blades are then preloaded relative to the base plate.

[0037] Furthermore, it can be provided that the base plate can have at least one slide, which is particularly useful for preventing the cutting device from tipping over. Tipping over of the cutting device would result in damage to the cutting edges of the first and second upper knives and the lower knife. Preferably, the slide is symmetrically arranged below the base plate. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The present invention will be described in detail below with the aid of the accompanying drawings.

[0039] Figure 1 Shows a three-dimensional overall view of the cutting device according to the present invention; Figure 2 shows the front part of a cutting device according to the invention; Figure 3 Show according to Figure 2 A cross section of the front portion of the cutting device; Figure 4 shows a top view of a lower knife having first and second upper knives; Figure 5 A side view of the upper and lower knives is shown; Figure 6 It shows that Figure 1 a side cutaway view of the front portion shown; Figure 7 The cutting device is shown placed on the ground; Figure 8 The cutting device is shown hanging from a wall; Fig. 9 The cutting equipment is shown positioned beneath the bush; Fig.10 A view showing two movable upper knives on a fixed lower knife, the lower knife having at least one opening arranged in the center of the lower knife; Fig.11 The illustration shows two movable upper knives on a fixed lower knife, which has an opening arranged in the center of the lower knife, wherein the upper knives are arranged close to one another. DETAILED DESCRIPTION

[0040] Figure 1 The cutting device 1 according to the invention is shown, which is preferably designed as a lawn mower. The cutting device 1 comprises a lever 10, by means of which the device 1 can be pushed by hand. The lever 10 has a handle 20. The handle 20 comprises a switch and, in the embodiment shown, a holder for a storage device, in particular a battery. According to the invention, it is provided that the lever 10 is connected to the cutting device by means of a rotatable joint, in particular a fixed joint 30.

[0041] Especially in Figure 2 and Figure 3 The two upper knives and the lower knife shown in FIG. 1 are part of a cutting tool. Figure 1 The hinge 30 can be used to bring the rod 10 into different positions relative to the cutting tool 50. How this can be utilized, for example, Figure 7 , 8 9. The entire cutting device with the cutting tool 50 can be guided at a constant distance from the ground via two running wheels 40, 41 arranged along an axis.

[0042] Figure 2The region of the cutting tool 50 is shown in detail with the lever 10 mounted on the cutting tool 50 via the articulation 30. Figure 1 Components which are identical have the same reference numerals. This applies in particular to the wheels 40, 41.

[0043] Attached to Figure 2 , showing the carriages 661, 662 on the underside of the base plate 650 (in Figure 6 ), they prevent the cutting device from tipping over and thus prevent the tips of the first and second upper knives and the lower knife from penetrating into the ground. In this way, damage to the blade is avoided. In addition, Figure 2 5 shows a capture area or discharge area of ​​the housing 550, which is used to collect the cut grass. If the device is tilted sideways, the collected grass is removed by the device in such a way that the grass does not accumulate in the area of ​​the upper and lower blades, but is guided away from the cutting mechanism or cutting device. This prevents the grass stems to be cut from bending.

[0044] Figure 3 Shown in cross-section Figure 1 and Figure 2 As can be seen from the cross-sectional view, the cutting tool includes a first upper blade 610 ( Figure 4 Middle) and second upper knife 620 ( Figure 4 ), which are rotatably arranged on the lower knife 600. The lower knife 600 is fixedly constructed. The first upper knife 610 and the second upper knife 620 are connected to the lower knife 600 via a rotation point 612 for the first upper knife and a rotation point 622 for the second upper knife.

[0045] The eccentric guide inserts 633, 643 with eccentric discs 531, 541 for the first and second upper knives are arranged on the Figure 4 . The first upper blade 610 and the second upper blade 620 are rotationally driven by means of an electric motor 510, which is fixedly mounted and acts on the central gear 520 directly by means of a motor pinion or pinion 515 without an intermediate connection, such as another transmission mechanism, such as a bevel gear transmission mechanism. The central gear 520 is in turn connected to a first gear 530 and a second gear 540, which rotationally drive the first upper blade and the second upper blade via an eccentric insert. The eccentric insert is Figure 4, shown in the drawing and denoted by the reference numerals 531 and 541. The eccentric disks 531, 541 are arranged in opposite directions, since the drive gears rotate in the same direction. The diameter and the number of teeth of the motor pinion 515 and the central gear 520 are coordinated with one another in such a way that a transmission ratio of 1 to 10 is ensured in the present case. This means that at a motor speed of 10,000 revolutions per minute under load, a frequency of 2·1000 cuts per minute is performed, since the blade cuts on both blade tooth flanks of the first and second upper knives. It has been shown that with this arrangement, the best cutting results are achieved, in particular in high-density grass and dense grass. In order to carry out the rotational eccentric movement by means of the first and second gears 530, 540, eccentric disks 531, 541 ( Figure 4 ). Figure 3 As shown, the drive gears 530, 540 are positioned so that the knives driven by them, i.e., the first upper knife 610 and the second upper knife 620, swing relative to each other. This measure can eliminate the lateral vibrations generated by the first upper knife 610 and the second upper knife 620 and minimize the vibrations generated thereby.

[0046] In order to achieve good cutting results in the center or in the middle region also with the cutting edge of the entire blade width of the lower blade provided by the first and second upper blades, Figure 4 The blades 601, 602, 603, 604, 605 for the lower knife 600 are arranged in the middle region aligned along the line 90. This means that all the blades 601, 602, 603, 604, 605 are on a line 90. In this regard, refer to Figure 4 In the front region of the central blade 601 of the lower blade 600, due to the shorter upper blades 614, 624, no grass is cut in this region by the rotational movement of the first and second upper blades 610, 620. However, if the central blade 601 of the lower blade is extended, the grass stems can be guided and then cut in the rear region of the upper blades 614, 624. As already mentioned above, particularly good cutting results are achieved when the first upper blade 610 and the second upper blade 620 are preloaded relative to the base plate forming the lower blade 600. The blades of the upper blades 610, 620 are marked with the reference numerals 614, 615, 616, 617, 618, 624, 625, 626, 627, 628.

[0047] These preloads can be determined in particular according to Figure 5 It can be seen from the diagram of . Figure 4 The lower knife 600 and the first and second upper knives 610, 620 are shown again in a top view. Figure 4 The opposing eccentric mechanisms 531 and 541 of the first upper knife 610 and the second upper knife 620 can be clearly seen.

[0048] In accordance with Figure 5 610 relative to the base plate 600, particularly good cutting results are achieved. In order to establish the prestressing, the eccentric guide inserts 633, 643 are provided with two spacers 635, 645, which produce the prestressing relative to the rotation point 612, so that the cutting edges of the upper and lower blades touch each other in every operating position. Each eccentric guide insert has two spacers 635, 645.

[0049] Figure 6 The cut-away side view of the cutting tool is shown. Identical components are given the same reference numerals as in the previous figures. The upright electric motor 510 with the pinion 515 can be clearly seen, wherein the pinion acts on the central gear 520. The central gear 520 then jointly drives the gear for the first upper knife and the gear for the second upper knife. The carriages 661, 662, by which the knives are kept at a distance from the ground, can also be clearly seen.

[0050] Figure 7 A first possible solution for storing the cutting device according to the invention is shown. To this end, the rod 10 is rotated upward about the rotation point 30 so that the cutting device according to the invention can be placed on the carriages 661, 662, for example in a garage.

[0051] As another alternative, Figure 8 As shown, by rotating the rod 10 about the rotation point 30, the device can be hung on a wall.

[0052] Fig. 9 It is shown how, by rotating the lever 10 about the rotation point 30 , the cutting device can be guided in a difficult-to-access position, for example, underneath a bush and thus cut the grass located thereunder.

[0053] Fig.10 and Fig.11 A particularly preferred embodiment of the cutting tool of the present invention is shown in detail, the cutting tool having two upper knives 610, 620, such as Figure 3 and Figure 4 As shown, the upper knife is rotatably configured on the lower knife 600, wherein the lower knife includes at least one opening 670 formed in the lower knife 600 for discharging cut grass.

[0054] It is usually the case that in cutting tools having upper blades 610 , 620 that oscillate in counter-movement, cut grass will be present between the upper blades 610 and 620 after a short operating time. Fig.10The two upper knives 610 and 620 are shown in the outer cutting position. If the two upper knives move towards each other, the corresponding blades 614 and 624 cut the grass blades and grass stems on the corresponding cutting sides of the blade 601 of the lower knife 600. The cutting knives 601 and 620 are limited on the lower side by the lower knife 600. At the top, the upper knives are limited by the cover 550 to protect the transmission mechanism from dirt and grass. In addition, a foam material seal (not shown) is provided below the cover 550 in the area of ​​the upper knives 610, 620 to close the air gap between the upper knives 610, 620 and the cover 550, which is determined by the design.

[0055] like Fig.11 As shown, if the upper knives 610, 620 move toward each other, the cut material is squeezed into the gap between the blades 614 and 624 and Fig.11 The cut material is pushed in the direction of the arrow A shown. This process is carried out in each reciprocating movement and due to the continuous re-extrusion of the squeezed cut material, the foam material seal that plays a shielding role cannot prevent the intrusion of the cut material. Therefore, according to the present invention, in a special embodiment, an opening 670 is provided in the lower knife 600, and the opening 670 is used to guide the cut material downward. In the embodiment shown, only a single opening 670 is provided, which is arranged in the center of the lower knife 610 in such a way that the opening 670 is centrally located between the two upper knives and before the transmission mechanism seal in the lower knife. Then, the cut material is guided downward through the opening 670 and the transmission mechanism remains free of dirt.

[0056] Of course, multiple openings may be provided instead of a single opening 670 without departing from the invention. However, the central positioning between the two upper blades 610, 620 is important for good grass discharge. The embodiment with the opening 670 described is the embodiment of the invention in Figure 3 and Figure 4 A special embodiment of a cutting tool is shown in , which has two upper knives 610 , 620 and a fixed lower knife 600 .

[0057] The invention firstly provides a mechanism by which very good cutting results can be achieved and by which a synchronous drive of several upper knives can be provided. In particular, edge regions with a width of 100 to 300 mm, in particular 200 mm, can be cut neatly in one direction in one process. Furthermore, a special embodiment of the invention is provided, by which the cut material can be easily discharged without clogging the cutting tool.

[0058] According to the Board of Appeal J15 / 55, the invention comprises the aspects disclosed in the following sentences, which are part of the description rather than the claims.

[0059] 1. A cutting device (1), in particular a lawn mowing device, preferably a lawn edge cutting device, comprising at least one cutting device, the cutting device having a knife assembly, the knife assembly comprising: At least one lower knife (600) and at least one upper knife (610, 620), the lower knife and the upper knife being movable relative to each other, preferably in a pivoting manner, wherein the at least one upper knife comprises at least one first upper knife (610) and a second upper knife (620), It is characterized in that The cutting device has a drive unit for a first upper knife (610) and a second upper knife (620), preferably in the form of an electric motor (510), and the drive unit is a common drive unit for at least the first upper knife (610) and the second upper knife (620).

[0060] 2. The cutting device according to claim 1, It is characterized in that The lower knife (600) is a fixed lower knife.

[0061] 3. A cutting device according to any one of the preceding clauses 1 to 3, It is characterized in that The first upper knife (610) and / or the second upper knife (620) are connected to the lower knife (600) via the first and second rotation points (612, 622).

[0062] 4. The cutting device according to claim 3, It is characterized in that The first upper knife (610) and the second upper knife (620) include a first eccentric guide insert (633) and a second eccentric guide insert (643).

[0063] 5. The cutting device according to any one of the preceding clauses 1 to 3, It is characterized in that The first upper knife (610) has a first gear (530) and / or the second upper knife (620) has a second gear (540).

[0064] 6. A cutting device according to any one of the preceding clauses 1 to 5, It is characterized in that The cutting device comprises a central gear (520) for driving a first gear (530) and a second gear (540).

[0065] 7. The cutting device according to any one of the preceding clauses 1 to 6, It is characterized in that The driving unit is connected to the central gear and is used to jointly drive the first and second upper knives (610, 620).

[0066] 8. A cutting device according to any one of the preceding clauses 1 to 7, It is characterized in that The drive unit comprises an electric motor (510) which preferably has a mechanical rated power in the range of 30 Watts to 100 Watts.

[0067] 9. A cutting device according to any one of the preceding clauses 1 to 8, It is characterized in that The electric motor (510) has an electric power of 40 watts to 200 watts.

[0068] 10. The cutting device according to any one of the preceding clauses 1 to 9, It is characterized in that The cutting width of the knife assembly is in the range of 100 mm to 400 mm.

[0069] 11. The cutting device according to any one of the preceding clauses 1 to 10, It is characterized in that Spacers (635, 645) are provided between the first and second upper knives (610, 620) and the lower knife (600) in such a way as to establish a preload of the first and second upper knives (610, 620).

[0070] 12. The cutting device according to any one of the preceding clauses 1 to 11, It is characterized in that Including the spacing provided by means of the spacer ( 635 ), in order to establish the preload, it lies in the range of 1 to 4 mm, preferably 3 mm.

[0071] 13. The cutting device according to any one of the preceding clauses 1 to 12, It is characterized in that The cutting device has at least two axially arranged running wheels (40, 50).

[0072] 14. A cutting device according to any one of the preceding clauses 1 to 13, It is characterized in that The cutting device comprises at least one rod (10) for guiding.

[0073] 15. The cutting device according to any one of the preceding clauses 1 to 14, It is characterized in that The rod (10) is arranged centrally on the cutting device and / or the cutting tool (50).

[0074] 16. The cutting device according to any one of the preceding clauses 1 to 15, It is characterized in that The lever (10) is connected to the cutting device by means of a joint (30), preferably a fixed joint, in particular a rotatable fixed joint.

[0075] 17. The cutting device according to any one of the preceding clauses 1 to 16, It is characterized in that The drive unit comprises at least one electric motor (510).

[0076] 18. The cutting device according to any one of the preceding clauses 1 to 17, It is characterized in that The electric motor is arranged vertically.

[0077] 19. A cutting device according to any one of the preceding clauses 1 to 18, It is characterized in that The electric motor includes a pinion gear (515).

[0078] 20. The cutting device according to any one of the preceding clauses 1 to 19, It is characterized in that The pinion gear (515) drives a central gear (520), and the central gear is connected to a first gear (530) and a second gear (540).

[0079] 21. A cutting device according to any one of the preceding clauses 1 to 20, It is characterized in that Both the pinion ( 515 ) and the central gear ( 520 ) each have a diameter and teeth.

[0080] 22. The cutting device according to any one of the preceding clauses 1 to 21, It is characterized in that The diameters and the number of teeth of the pinion (515) and the central gear (520) are coordinated with one another in such a way that a transmission ratio of between 1:5 and 1:50, preferably 1:10, is achieved.

[0081] 23. A cutting device according to any one of the preceding clauses 1 to 22, It is characterized in that The first and second gears (530, 540) are positioned such that the first and second upper knives (610, 620) driven by the first and second gears (530, 540) swing relative to each other.

[0082] 24. A cutting device according to any one of the preceding clauses 1 to 23, It is characterized in that The lower knife has a plurality of blades.

[0083] 25. The cutting device according to any one of the preceding clauses 1 to 24, It is characterized in that The lower knife (600) comprises a middle area and first and second edge areas.

[0084] 26. A cutting device according to any one of the preceding clauses 1 to 25, It is characterized in that The blades (601, 602, 603, 604, 605) of the lower knife are aligned in the middle area.

[0085] 27. A cutting device according to any one of the preceding clauses 1 to 26, It is characterized in that The blade (614, 615, 616, 617, 618, 624, 625, 626, 627, 628) of the upper knife is shortened.

[0086] 28. A cutting device according to any one of the preceding clauses 1 to 27, It is characterized in that The cutting device comprises a base plate (600).

[0087] 29. A cutting device according to any one of the preceding clauses 1 to 28, It is characterized in that The first and second upper knives (610, 620) comprise a front region and a rear region, and the spacer (635) is arranged such that the first and second upper knives (610, 620) are prestressed relative to the lower knife (600) in the rear region.

[0088] 30. A cutting device according to any one of the preceding clauses 1 to 29, It is characterized in that At least one slide (660, 662), in particular a skid, is arranged below the base plate (600).

Claims

1. A cutting device (1), in particular a lawn mowing device, preferably a lawn edge cutting device, comprising at least one cutting device, the cutting device having a knife assembly, the knife assembly comprising: At least one lower knife (600) and at least one upper knife (610, 620), the lower knife and the upper knife being movable relative to each other, preferably in a pivoting manner, wherein the at least one upper knife comprises at least one first upper knife (610) and a second upper knife (620), It is characterized in that The cutting device has a drive unit for a first upper knife (610) and a second upper knife (620), preferably in the form of an electric motor (510), and the drive unit is a common drive unit for at least the first upper knife (610) and the second upper knife (620), and the drive unit includes at least three gears, wherein the three gears include two gears of substantially the same size, in particular gears of substantially the same diameter, namely a first gear (530) and a second gear (540) each having an eccentric disk (531, 541), and a third central gear is constructed for meshing with the first gear (530) and the second gear (540), wherein the third central gear (520) is connected to a pinion (515) of the electric motor.

2. The cutting device according to claim 1, characterized in that The lower knife (600) is a fixed lower knife.

3. The cutting device according to claim 1, characterized in that The lower knife has at least one opening (670), which is preferably in the region between the first and second upper knife (610, 620), particularly preferably in the center between the first and second upper knife (610, 620).

4. Cutting device according to any one of the preceding claims 1 to 3, characterized in that The first upper knife (610) and / or the second upper knife (620) are connected to the lower knife (600) via the first and second rotation points (612, 622).

5. The cutting device according to claim 4, characterized in that The first upper knife (610) and the second upper knife (620) include a first eccentric guide insert (633) and a second eccentric guide insert (643).

6. The cutting device according to any one of claims 1 to 5, characterized in that The drive unit comprises an electric motor (510) which preferably has a mechanical rated power in the range of 30 Watts to 100 Watts and / or consumes an electrical power of 40 Watts to 200 Watts.

7. The cutting device according to any one of claims 1 to 6, characterized in that Spacers (635, 645) are provided between the first and second upper knives (610, 620) and the lower knife (600) in such a way as to establish a preload of the first and second upper knives (610, 620).

8. The cutting device according to any one of claims 1 to 7, characterized in that The cutting device comprises at least one rod (10) for guiding and / or the rod (10) is connected to the cutting device by means of a joint (30), preferably a fixed joint, in particular a rotatable fixed joint.

9. The cutting device according to any one of claims 1 to 8, characterized in that The drive unit comprises at least one electric motor (510), which is preferably arranged vertically and comprises in particular a pinion (515).

10. The cutting device according to any one of claims 1 to 9, characterized in that The first upper knife and the second upper knife comprise a front region and a rear region, and the spacers (635, 645) are arranged such that the first upper knife and the second upper knife are prestressed relative to the lower knife in the rear region.

11. The cutting device according to any one of claims 1 to 10, characterized in that A spacer (635) is provided between the first and second upper knives (610, 620) and the lower knife (600) so as to establish a preload of the first and second upper knives, and in particular the spacing between the upper knife and the lower knife set by means of the spacer (635) is in the range of 1 to 4 mm, preferably 3 mm, in order to establish the preload.

12. The cutting device according to any one of claims 1 to 11, characterized in that The electric motor comprises a pinion (515), wherein both the pinion (515) and the central gear (520) each have a diameter and teeth, and / or The diameters and the number of teeth of the pinion (515) and the eccentric discs (531, 541) are coordinated with one another so that a transmission ratio of 1:10 is achieved and / or a transmission ratio of 1:5.9 is achieved for the pinion (515) and / or the central gear (520).

13. The cutting device according to any one of claims 1 to 10, characterized in that The lower knife (600) comprises a middle area and first and second edge areas.

14. The cutting device according to any one of claims 1 to 13, characterized in that The blades (601, 602, 603, 604, 605) of the lower knife are aligned in the middle region and / or the blades (614, 615, 616, 617, 618, 624, 625, 626, 627, 628) of the upper knife are shortened.

15. The cutting device according to any one of claims 1 to 14, characterized in that The first and second upper knives (610, 620) comprise a front region and a rear region, and the spacer (635) is arranged such that the first and second upper knives (610, 620) are prestressed relative to the lower knife (600) in the rear region.

16. The cutting device according to any one of claims 1 to 13, characterized in that The cutting device has a storage device, in particular an electrical storage device, in particular a battery, preferably a battery with 18 volts, 2.5 ampere-hours (Ah) and an energy of 45 watt-hours having an operating time of 20 to 200 minutes, in particular 40 to 80 minutes, in particular 40 to 50 minutes, and / or the cutting device without the storage device, in particular the battery, has a weight of 2.0 kg to 3.0 kg, preferably 2.4 kg.

17. A cutting device (1), in particular a lawn mowing device, preferably a lawn edge cutting device, There is at least one cutting device, the cutting device having a knife assembly, the knife assembly comprising: At least one lower knife (600) and at least one upper knife (610, 620), the lower knife and the upper knife being movable relative to each other, preferably in a pivoting manner, wherein the at least one upper knife comprises at least one first upper knife (610) and a second upper knife (620), It is characterized in that The cutting device has a drive unit for a first upper knife (610) and a second upper knife (620), preferably in the form of an electric motor (510), and the drive unit is a common drive unit for at least the first upper knife (610) and the second upper knife (620), and the lower knife includes at least one opening.

18. The cutting device according to claim 17, characterized in that The opening is the only opening (670), and the opening is arranged substantially centrally between the first upper knife (610) and the second upper knife (620).

19. The cutting device according to any one of claims 17 to 18, characterized in that The cutting device comprises a covering portion (550) above the first and second upper knives (610, 620).

20. The cutting device according to any one of claims 17 to 19, characterized in that The cutting device comprises a seal, preferably a foam seal.

21. The cutting device according to claim 20, characterized in that The seal is arranged in such a way that it is located below the cover and closes an air gap between the first and second upper blades (610, 620) and the cover (550).

22. A cutting device according to any one of claims 17 to 21, characterised in that The lower knife (600) is a fixed lower knife.

23. Cutting device according to any one of the preceding claims 17 to 22, characterized in that The first upper knife (610) and / or the second upper knife (620) are connected to the lower knife (600) via a first and a second rotation point (612, 622).

24. Cutting device according to any one of claims 17 to 23, characterized in that The first upper knife (610) and the second upper knife (620) include a first eccentric guide insert (633) and a second eccentric guide insert (643).

25. Cutting device according to any one of claims 17 to 24, characterized in that The drive unit comprises an electric motor (510) which preferably has a mechanical rated power in the range of 30 Watts to 100 Watts and / or consumes an electrical power of 40 Watts to 200 Watts.

26. Cutting device according to any one of claims 17 to 25, characterized in that Spacers (635, 645) are provided between the first and second upper knives (610, 620) and the lower knife (600) in such a way as to establish a preload of the first and second upper knives (610, 620).

27. Cutting device according to any one of claims 17 to 26, characterized in that The cutting device comprises at least one rod (10) for guiding and / or the rod (10) is connected to the cutting device by means of a joint (30), preferably a fixed joint, in particular a rotatable fixed joint.

28. Cutting device according to any one of claims 17 to 27, characterized in that The drive unit comprises at least one electric motor (510), which is preferably arranged vertically and comprises in particular a pinion (515).

29. The cutting device according to any one of claims 17 to 28, characterized in that The first upper knife and the second upper knife comprise a front region and a rear region, and the spacers (635, 645) are arranged such that the first upper knife and the second upper knife are prestressed relative to the lower knife in the rear region.

30. Cutting device according to any one of claims 17 to 29, characterized in that A spacer (635) is provided between the first and second upper knives (610, 620) and the lower knife (600) in order to establish a preload of the first and second upper knives, in particular the distance between the upper knife and the lower knife arranged by means of the spacer (635) is in the range of 1 to 4 mm, preferably 3 mm, in order to establish the preload.

31. A cutting device according to any one of claims 17 to 30, characterised in that The electric motor comprises a pinion (515), wherein both the pinion (515) and the central gear (520) each have a diameter and teeth, and / or The diameters and the number of teeth of the pinion (515) and the eccentric discs (531, 541) are coordinated with one another in such a way that a transmission ratio of 1:10 and / or a transmission ratio of 1:5.9 between the pinion (515) and the central gear is achieved.

32. Cutting device according to any one of claims 17 to 31, characterized in that The lower knife (600) comprises a middle area and first and second edge areas.

33. A cutting device according to any one of claims 17 to 32, characterised in that The cutting edges (601, 602, 603, 604, 605) of the lower knife are aligned in the middle region and / or the cutting edges (614, 615, 616, 617, 618, 624, 625, 626, 627, 628) of the upper knife are shortened.

34. Cutting device according to any one of claims 17 to 33, characterized in that The first and second upper knives (610, 620) comprise a front region and a rear region, and the spacer (635) is arranged such that the first and second upper knives (610, 620) are prestressed relative to the lower knife (600) in the rear region.

35. Cutting device according to any one of claims 17 to 34, characterized in that The cutting device is a storage device, in particular an electrical storage device, in particular a battery, a battery with 18 volts, 2.5 ampere-hours (Ah) and an energy of 45 watt-hours, preferably with an operating time of 20 to 200 minutes, in particular 40 to 80 minutes, in particular 40 to 50 minutes, and / or the cutting device without the storage device, in particular the battery, has a weight of 2.0 kg to 3.0 kg, preferably 2.4 kg.

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