Cutting means attachment device, cutting device and lawn mower

Abstract

The invention is based on a cutting means fastening device (10a - 10e) for a cutting device (12a - 12e), in particular for a lawnmower (14a), preferably for an autonomous lawnmower, with a bearing unit (16a - 16e) for rotatably supporting a cutting element (18a - 18e) of the cutting device (12a - 12e) about an axis of rotation (20a - 20e), wherein a bearing surface (22a - 22e) of the bearing unit (16a - 16e) has a bearing surface portion (26a - 26e) angled in the axial direction (24a - 24e) relative to the axis of rotation (20a - 20e). It is proposed that a ratio of a maximum longitudinal extent (32a - 32e) of the angled bearing surface portion (26a - 26e) parallel to the rotation axis (20a - 20e) to a maximum longitudinal extent (30a - 30e) of the bearing surface (22a - 22e) parallel to the rotation axis (20a - 20e) is at least 0.30.

Description

State of the art

[0001] A cutting means fastening device for a cutting device with a bearing unit for rotatably supporting a cutting element of the cutting device about a rotation axis, wherein a bearing surface of the bearing unit has a bearing surface portion angled in the axial direction relative to the rotation axis, has already been proposed. Disclosure of the invention

[0002] The invention is based on a cutting means fastening device for a cutting device, in particular for a lawn mower, preferably for an autonomous lawn mower, with a bearing unit for rotatably supporting a cutting element of the cutting device about a rotation axis, wherein a bearing surface of the bearing unit has a bearing surface portion angled in the axial direction relative to the rotation axis.

[0003] It is proposed that a ratio of a maximum longitudinal extent of the angled bearing surface portion parallel to the rotation axis to a maximum longitudinal extent of the bearing surface parallel to the rotation axis is at least 0.30, preferably at least 0.5, preferably at least 0.7 and particularly preferably at least 0.9.

[0004] The inventive design of the cutting means fastening device allows for particularly high user comfort. Advantageously, a cutting element can be secured in a specific position in at least one operating state. Advantageously, unwanted axial movement relative to the rotational axis of the cutting element can be counteracted. Advantageously, rattling of the cutting element during operation of the cutting device can be counteracted. Advantageously, unwanted noise generation can be counteracted. A particularly pleasant user experience can be realized.

[0005] The cutting means fastening device is preferably designed as a single, two, or three-part device. Alternatively, it is conceivable for the cutting means fastening device to consist of more than three parts. The cutting means fastening device preferably has, in particular in at least one embodiment, two fastening elements. The bearing unit is preferably formed by one fastening element of the two fastening elements. The fastening element is preferably provided for fastening, in particular directly, to a cutting disc of the cutting device. It is conceivable for the fastening element to be detachably fastened to the cutting disc. In this context, “detachably” should be understood to mean, in particular, “non-destructively separable.” Alternatively, however, it is also conceivable for the fastening element to be formed at least partially in one piece with the cutting disc.The term "at least one unit or object and at least one further unit or object are at least partially formed integrally with one another" should be understood in particular to mean that at least one element of the unit or object is formed integrally with at least one further element of the further unit or object. "Integral" can be understood to mean at least materially connected, for example by a welding process, a soldering process, an adhesive process, an injection molding process and / or another process that appears appropriate to a person skilled in the art, and / or advantageously formed in one piece, for example by production from a cast and / or by production using a single-component or multi-component injection molding process and advantageously from a single blank.It is also conceivable that the knife disc, particularly in the first embodiment, is part of the cutting means fastening device.

[0006] The cutting means fastening device preferably has a stop element. The stop element is provided in particular for axially securing the cutting element in the axial direction with respect to the axis of rotation. The stop element is preferably formed, in particular in the at least one embodiment, by a further fastening element of the two fastening elements. The fastening element and the further fastening element are preferably detachably connectable to one another, in particular fastenable to one another, for example by means of a screw connection, a snap-in connection, a clamping connection, a bayonet connection, or the like. In the at least one embodiment in particular, the further fastening element is designed in a screw-like manner, preferably as a screw, or in a bolt-like manner.

[0007] The bearing unit has at least one bearing element. It is also conceivable for the bearing unit to have two or more than two bearing elements. The bearing surface is formed by the at least one bearing element. It is conceivable for the bearing element to be formed separately from the fastening element and / or the additional fastening element. Alternatively, it is also conceivable for the bearing element to be formed integrally with the fastening element or the additional fastening element.

[0008] Alternatively, it is also conceivable, in particular in at least one further embodiment of the cutting means fastening device, for the cutting means fastening device to have only one fastening element, wherein the stop element and / or the bearing unit are / is formed in particular by the fastening element. Preferably, in the at least one further embodiment, the bearing unit is formed integrally with the stop element. The fastening element is preferably designed in the at least one further embodiment as a screw, preferably as a screw, or as a bolt.

[0009] The cutting element is preferably designed as a cutting blade, in particular as a lawnmower cutting blade. The cutting element preferably has a fixing recess. The bearing unit is preferably arranged in the fixing recess by means of the cutting means fastening device when the cutting element is mounted on the cutting device. The stop element preferably has a stop surface against which the cutting element preferably rests, preferably flatly, preferably in the axial direction, in a fixed position of the cutting element. A main extension plane of the stop surface preferably runs at least substantially perpendicular to the axis of rotation.A "main extension plane" of a structural unit or element can be understood as a plane that is parallel to a largest side surface of the smallest possible imaginary cuboid that just completely encloses the structural unit, and in particular runs through the center of the cuboid. "Substantially perpendicular" can be understood as an alignment of a direction relative to a reference direction, wherein the direction and the reference direction, in particular viewed in a projection plane, enclose an angle of 90°, and the angle has a maximum deviation of in particular less than 8°, advantageously less than 5°, and particularly advantageously less than 2°.

[0010] "Intended" should be understood as specifically configured, specifically designed, and / or specifically equipped. The fact that an object is intended for a specific function should be understood as meaning that the object fulfills and / or performs this specific function in at least one application and / or operating state.

[0011] The angled bearing surface portion can have at least a partially straight profile and / or at least a partially curved profile. The bearing surface extends from the stop element, in particular from the stop surface, to an end of the angled bearing surface portion of the bearing surface remote from the stop element. It is conceivable that the bearing surface is formed entirely by the angled bearing surface portion. The angled bearing surface portion delimits the bearing surface parallel to the axis of rotation at least on one side, in particular in at least one embodiment on both sides.

[0012] The maximum extension of the bearing surface parallel to the rotation axis preferably runs from the stop element, in particular the stop surface, across the angled bearing surface portion to one end of the angled bearing surface portion. Preferably, a distance of the angled bearing surface portion, in particular in the at least one embodiment, from the stop element, preferably from the stop surface, parallel to the rotation axis, is smaller than a thickness of the cutting element, preferably at least as a thickness of the cutting element in the region of the fixing recess.

[0013] It is further proposed that the bearing unit, in particular by means of the angled bearing surface portion, is provided to move the cutting element in at least one drive state with a force acting axially with respect to the axis of rotation in the direction of a fixed position, wherein the cutting element in the fixed position has at least one contact point with the angled bearing surface portion. A particularly efficient and / or reliable fixing of the cutting element can be achieved. Advantageously, the generation of undesirable noises due to rattling of the cutting element in the at least one drive state can be counteracted particularly reliably. Preferably, the cutting device, in particular the knife disk, rotates about a drive axis in the at least one drive state.The drive axis preferably runs at least substantially perpendicular to a main extension plane of the cutting disk and / or through a geometric center of the cutting disk. The drive axis runs, in particular, at least substantially parallel to the axis of rotation and is preferably offset from the axis of rotation. "Substantially parallel" can be understood here as an alignment of a direction relative to a reference direction, in particular in a plane, wherein the direction has a deviation from the reference direction of, in particular, less than 8°, advantageously less than 5°, and particularly advantageously less than 2°.The at least one cutting element is provided, in the at least one drive state, in particular as a result of the drive of the cutting device, preferably the knife disk, about the drive axis, in particular by an acting centrifugal force, preferably radially outwards with respect to the drive axis, to be pressed against the bearing unit, preferably against the angled bearing surface portion, preferably with a surface of the cutting element delimiting the fixing recess. It is conceivable that the fixed position is defined by the stop element, preferably the stop surface, wherein the cutting element preferably abuts, in particular rests, against the stop element, in particular the stop surface, in the fixed position. Alternatively, however, it is also conceivable that the fixed position is defined independently of the stop element, merely by a profile of the angled bearing surface portion.It is also conceivable that the cutting element in the fixed position in the at least one drive state has two contact points with the angled bearing surface portion.

[0014] It is further proposed that the angled bearing surface portion has an angle of at least 20° and at most 60° to the axis of rotation. Advantageously, a particularly efficient and / or reliable positioning of the cutting element can be achieved. The occurrence of disturbing noises due to clattering of the cutting element in the at least one drive state can be counteracted particularly efficiently and / or reliably. The angle is preferably at least 30°. Preferably, the angle is at most 50°, preferably at most 40°. Particularly preferably, the angle is at least substantially 35°. In this context, the fact that a variable at least substantially corresponds to a predetermined value should be understood to mean in particular that a deviation from the predetermined value deviates in particular by less than 25%, preferably less than 10% and particularly preferably less than 5% of the predetermined value.

[0015] It is also proposed that the bearing surface form a wedge shape or a concave shape, in particular a C-shape or a U-shape, particularly due to the angled bearing surface portion. Advantageously, a particularly low-friction positioning of the cutting element can be achieved. Tilting and / or impact of the cutting element can be counteracted particularly efficiently. The generation of disturbing noises due to clattering of the cutting element in at least one drive state can be counteracted particularly efficiently and / or reliably.

[0016] It is further proposed that the fixed position be arranged at a distance in the axial direction from at least one end, preferably from the ends of the bearing surface. Advantageously, a particularly low-friction positioning of the cutting element can be achieved. Tilting and / or striking of the cutting element can be counteracted particularly efficiently. The generation of disturbing noises due to clattering of the cutting element in the at least one drive state can be counteracted particularly efficiently and / or reliably. Preferably, the angled bearing surface portion is spaced from one end of the bearing surface and / or the stop element, in particular the stop surface.

[0017] It is further proposed that the cutting means fastening device comprise a stop element, in particular the one already mentioned, against which the cutting element rests in the fixed position, in particular flatly, wherein the cutting element in the fixed position in the at least one drive state is subjected to the axially acting force in the direction of the stop element, preferably the stop surface. Advantageously, a particularly secure contact of the cutting element with the stop element can be supported. The occurrence of disturbing noises due to clattering of the cutting element in the at least one drive state can be counteracted particularly efficiently and / or reliably.Preferably, the cutting element in the fixed position rests against the stop surface, in particular flatly, wherein in particular the cutting element in the fixed position in the at least one drive state is subjected to the axially acting force in the direction of the stop element, preferably the stop surface.

[0018] It is also proposed that at least part of the bearing unit is made of a material, in particular a non-ferrous metal, preferably brass, which is different from a material from which the stop element is made. Advantageously, a particularly wear-resistant bearing unit can be provided. A particularly durable cutting means fastening device can be realized. Advantageously, a bearing unit with particularly good sliding properties can be provided. Particularly reliable positioning of the cutting element in the fixed position can be achieved by means of the angled bearing surface portion. A cutting means fastening device with particularly advantageous bearing properties and, at the same time, particularly low manufacturing costs can be realized. The stop element is made of iron or steel, for example.Alternatively, however, it is also conceivable for the stop element to be made of a different material that would be considered appropriate by a person skilled in the art. Preferably, the at least one bearing element is made of a material, in particular a non-ferrous metal, preferably brass, that is different from the material from which the stop element is made. Alternatively, however, it is also conceivable for at least the part of the bearing unit, in particular the bearing element, and the stop element to be made of the same material.

[0019] It is further proposed that at least one part of the bearing unit, in particular the part already mentioned above, in particular the at least one bearing element, is screwed onto the stop element. Advantageously, at least the part of the bearing unit can be replaced particularly cost-effectively. Particularly simple and / or cost-effective adaptation to different requirements, for example different cutting elements, can be made possible by flexible replacement of at least the part of the bearing unit. Preferably, at least the part of the bearing unit, in particular the bearing element, can be screwed onto the stop element up to a stop on the stop surface of the stop element or can be screwed onto the stop element up to a stop on the further bearing element.The stop element, in particular the additional fastening element, preferably has a thread, which is provided, in particular, for fastening the bearing element to the stop element, preferably the fastening element, and which cooperates with a thread of the bearing element. It is conceivable that the bearing surface is formed by two bearing elements, one of which can be screwed onto the stop unit. The bearing elements preferably adjoin one another in an assembled state, preferably to form the continuous bearing surface.

[0020] Furthermore, a cutting device, in particular the one already mentioned above, with at least one cutting means fastening device, in particular the one already mentioned above, and with at least one cutting element, in particular the one already mentioned above, is proposed. The design of the cutting device according to the invention makes it possible to achieve particularly high user comfort. Advantageously, in at least one operating state, the cutting element can be fixed in a specific position. Advantageously, an undesired axial movement with respect to the axis of rotation of the cutting element can be counteracted. Advantageously, rattling of the cutting element during operation of the cutting device can be counteracted. Advantageously, an undesired noise development can be counteracted. A particularly pleasant user experience can be realized.The cutting device preferably has a plurality of cutting means fastening devices. The cutting device preferably has a plurality of cutting elements. Particularly preferably, a number of cutting means fastening devices corresponds to a number of cutting elements. The cutting means fastening devices are preferably arranged around the drive axis, preferably at the same distance from the drive axis. The cutting means fastening devices are preferably arranged uniformly around the drive axis. Alternatively, however, it is also conceivable for the distances between the drive axis and the cutting means fastening devices to differ and / or for the cutting means fastening devices to be arranged unevenly around the drive axis.

[0021] It is also proposed that the cutting device has a knife disk, in particular the one already mentioned above, to which the cutting element can be fastened by means of the cutting means fastening device, wherein a stop surface of the cutting means fastening device, in particular running at least substantially perpendicular to the axis of rotation, preferably the one already mentioned above, is arranged at an end of the bearing surface remote from the knife disk. Advantageously, a particularly advantageous positioning of the cutting element can be achieved. A particularly reliable avoidance of disturbing noises by the cutting element can be achieved. Preferably, the fixed position, in particular in the at least one exemplary embodiment, is arranged at the end of the bearing surface remote from the knife disk.

[0022] Furthermore, it is proposed that a minimum diameter of a fixing recess of the cutting element, in particular of the aforementioned one, be smaller than a maximum extension of the stop surface. Advantageously, the cutting element can be connected to the cutting disc in a particularly captively secure manner. This allows for particularly high user safety. The maximum extension of the stop surface is preferably measured in a plane parallel to the main extension plane of the stop surface.

[0023] Furthermore, a lawnmower, in particular the one already mentioned, in particular an autonomous lawnmower, with a cutting device, in particular the one already mentioned, is proposed. The inventive design of the lawnmower makes it possible to achieve particularly high user comfort. Advantageously, in at least one operating state, the cutting element can be fixed in a specific position. Advantageously, an undesired axial movement with respect to the axis of rotation of the cutting element can be counteracted. Advantageously, rattling of the cutting element during operation of the cutting device can be counteracted. Advantageously, an undesired noise development can be counteracted. A particularly pleasant user experience can be realized. The lawnmower can be designed as an autonomous lawnmower and / or as a manually operated lawnmower.

[0024] The cutting means fastening device according to the invention, the cutting device according to the invention, and / or the lawnmower according to the invention are not intended to be limited to the application and embodiment described above. In particular, the cutting means fastening device according to the invention, the cutting device according to the invention, and / or the lawnmower according to the invention can have a number of individual elements, components, and units that differs from the number stated herein in order to fulfill a function described herein. Furthermore, in the value ranges specified in this disclosure, values ​​within the stated limits are also to be considered disclosed and can be used arbitrarily. drawing

[0025] Further advantages will become apparent from the following description of the drawings. The drawings illustrate five exemplary embodiments of the invention. The drawings, the description, and the claims contain numerous features in combination. Those skilled in the art will also expediently consider the features individually and combine them into useful further combinations.

[0026] They show: Fig. 1 a lawnmower in a perspective view, Fig. 2 a part of a cutting device of the lawn mower from Fig. 1 with a cutting means fastening device and a cutting element in a perspective view, Fig. 3 the cutting means fastening device and the cutting element Fig. 2 in a cross-sectional view, Fig. 4 a cutting means fastening device and a cutting element in a first alternative embodiment in a cross-sectional view, Fig. 5 a cutting means fastening device and a cutting element in a second alternative embodiment in a cross-sectional view, Fig. 6 a cutting means fastening device and a cutting element in a third alternative embodiment in a cross-sectional view and Fig. 7 a cutting means fastening device and a cutting element in a fourth alternative embodiment in a cross-sectional view. Description of the embodiments

[0027] Fig. 1 shows a lawnmower 14a. The lawnmower 14a has a cutting device 12a. The lawnmower 14a is embodied here, for example, as an autonomous lawnmower. Alternatively, it is conceivable that the lawnmower 14a is embodied as a manually operated lawnmower.

[0028] The cutting device 12a has a plurality of cutting means fastening devices 10a and a plurality of cutting elements 18a (cf. Fig. 2, in the figures of the exemplary embodiment a, only one cutting element 18a of the plurality of cutting elements 18a and one cutting means fastening device 10a of the plurality of cutting means fastening devices 10a are shown. The cutting device 12a has a knife disk 42a, to which the cutting elements 18a can be fastened by means of the cutting means fastening devices 10a.

[0029] In Fig. 3 shows, by way of example, a cutting means fastening device 10a of the plurality of cutting means fastening devices 10a and a cutting element 18a of the plurality of cutting elements 18a. The cutting means fastening device 10a has a bearing unit 16a for rotatably supporting the cutting element 18a about a rotation axis 20a.

[0030] The cutting means fastening device 10a is designed in two parts. Alternatively, however, it is also conceivable for the cutting means fastening device 10a to be designed in one or three parts, or to consist of more than three parts. It is also conceivable for the knife disk 42a to be part of the cutting means fastening device 10a.

[0031] The cutting means fastening device 10a has two fastening elements 52a, 54a. The bearing unit 16a is formed by one fastening element 52a of the two fastening elements 52a, 54a. The bearing unit 16a has a bearing element 60a. The bearing element 60a is formed by the fastening element 52a.

[0032] The fastening element 52a is intended for attachment, in particular directly, to the cutting disc 42a. It is conceivable that the fastening element 52a can be detachably attached to the cutting disc 42a. Alternatively, however, it is also conceivable that the fastening element 52a is at least partially formed integrally with the cutting disc 42a. It is also conceivable that the cutting disc 42a is part of the cutting means attachment device 10a.

[0033] The bearing unit 16a has a bearing surface 22a. The bearing element 60a has the bearing surface 22a. The bearing surface 22a has a bearing surface portion 26a that is angled in the axial direction 24a relative to the rotation axis 20a. The bearing element 60a has the angled bearing surface portion 26a.

[0034] The ratio of a maximum longitudinal extent 32a of the angled bearing surface portion 26a parallel to the rotation axis 20a to a maximum longitudinal extent 30a of the bearing surface 22a parallel to the rotation axis 20a is at least 0.30. The bearing surface 22a is completely formed by the angled bearing surface portion 26a.

[0035] The cutting means fastening device 10a has a stop element 40a. The stop element 40a is provided for axially securing the cutting element 18a in the axial direction 24a relative to the rotation axis 20a. The knife disk 42a and / or the fastening element 52a is provided for axially securing the cutting element 18a in a further axial direction 56a relative to the rotation axis 20a. The further axial direction 56a runs opposite to the axial direction 24a.

[0036] The stop element 40a is formed by a further fastening element 54a of the two fastening elements 52a, 54a. The fastening element 52a and the further fastening element 54a can be releasably connected to one another, in particular fastened to one another, for example by means of a screw connection, a snap-in connection, a clamp connection, a bayonet connection, or the like. The further fastening element 54a is designed as a screw, preferably as a screw.

[0037] The cutting element 18a has a fixing recess 48a. When the cutting element 18a is mounted on the cutting device 12a, the bearing unit 16a is arranged in the fixing recess 48a by means of the cutting means fastening device 10a. The stop element 40a has a stop surface 44a. When the cutting element 18a is in a fixed position, the cutting element 18a rests, preferably flatly, against the stop surface 44a (see FIG. Fig. 3). A main extension plane of the stop surface 44a runs at least substantially perpendicular to the rotation axis 20a.

[0038] A minimum diameter 46a of the fixing recess 48a of the cutting element 18a is smaller than a maximum extension 50a of the stop surface 44a. The maximum extension 50a of the stop surface 44a is measured in a plane parallel to the main extension plane of the stop surface 44a.

[0039] The angled bearing surface portion 26a has a straight profile. The bearing surface 22a extends from the stop element 40a, in particular from the stop surface 44a, to an end of the angled bearing surface portion 26a remote from the stop element 40a, in particular the stop surface 44a. The stop surface 44a is formed by a screw head of the further fastening element 54a, which is designed as a screw.

[0040] A distance of the angled bearing surface portion 26a to the stop element 40a, in particular to the stop surface 44a, parallel to the rotation axis 20a, is smaller than a thickness of the cutting element 18a, preferably at least than a thickness of the cutting element 18a in the region of the fixing recess 48a.

[0041] The bearing unit 16a, in particular by means of the angled bearing surface portion 26a, is provided to move the cutting element 18a in at least one drive state with a force acting axially with respect to the rotation axis 20a in the direction of a fixed position, wherein the cutting element 18a in the fixed position has at least one contact point 34a with the angled bearing surface portion 26a.

[0042] The cutting device 12a, in particular the knife disk 42a, rotates in the at least one drive state about a drive axis (not shown here). The drive axis runs at least substantially perpendicular to a main extension plane of the knife disk 42a and / or through a geometric center of the knife disk 42a. The drive axis runs at least substantially parallel to the axis of rotation 20a. The drive axis is arranged offset from the axis of rotation 20a. The cutting element 18a is provided, in the at least one drive state, in particular as a result of the drive of the cutting device 12a, preferably the knife disk 42a, about the drive axis, by a centrifugal force acting in the drive state, to be pressed radially outward with respect to the drive axis against the bearing unit 16a, preferably against the angled bearing surface portion 26a.

[0043] The angled bearing surface portion 26a has an angle 36a of at least 20° and at most 60° to the rotation axis 20a. The angle 36a is 35° here, for example.

[0044] In the fixed position, the cutting element 18a rests, in particular flatly, against the stop element 40a, in particular against the stop surface 44a. In the fixed position, in at least one drive state, the cutting element 18a is subjected to the axially acting force in the direction of the stop element 40a, in particular the stop surface 44a.

[0045] The stop surface 44a of the cutting means fastening device 10a is arranged at an end 38a of the bearing surface 22a remote from the cutting disc 42a. The stop surface 44a extends at least substantially perpendicular to the rotational axis 20a. The stop surface 44a is arranged at an end 38a of the bearing surface 22a remote from the cutting disc 42a.

[0046] In the Fig. Four further embodiments of the invention are shown in Figures 4 to 7. The following descriptions and the drawings are essentially limited to the differences between the embodiments, whereby with regard to components with the same designation, in particular with regard to components with the same reference numerals, reference is also made in principle to the drawings and / or the description of the other embodiments, in particular to the Fig. 1 to 3. To distinguish the embodiments, the letter a is added to the reference numerals of the embodiment in the Fig. 1 to 3. In the examples of the Fig. 4 to 7 the letter a is replaced by the letters b to e.

[0047] Fig. 4 shows a portion of a cutting device 12b with a cutting means fastening device 10b and with a cutting element 18b. The cutting means fastening device 10b has a bearing unit 16b for rotatably supporting the cutting element 18b about a rotation axis 20b.

[0048] The bearing unit 16b has a bearing surface 22b. The bearing surface 22b has a bearing surface portion 26b that is angled in the axial direction 24b relative to the rotation axis 20b. The bearing unit 16b has two bearing elements 60b, 62b. One bearing element 60b of the two bearing elements 60b, 62b has, for example, the angled bearing surface portion 26b. Another bearing element 62b of the two bearing elements 60b, 62b has, for example, a circular-cylindrical bearing surface portion 58b. The further bearing element 62b is formed integrally with a stop element 40b of the cutting means fastening device 10b, in particular a fastening element 52b of the cutting means fastening device 10b. The bearing surface 22b is formed by the two bearing elements 60b, 62b, in particular by the circular cylindrical bearing surface portion 58b and the angled bearing surface portion 26b.

[0049] A ratio of a maximum longitudinal extension 32b of the angled bearing surface portion 26b parallel to the rotation axis 20b to a maximum longitudinal extension 30b of the bearing surface 22b parallel to the rotation axis 20b is at least 0.30.

[0050] The fastening element 52b is provided for direct attachment to a cutting disc 42b of the cutting device 12b, here, for example, by means of a screw connection. The fastening element 52b has a thread. The cutting disc 42b has a thread. The thread of the fastening element 52b is provided for attachment to the cutting disc 42b and cooperates with the thread of the cutting disc 42b.

[0051] At least part of the bearing unit 16b is made of a material, in particular a non-ferrous metal, preferably brass, which is different from a material from which the stop element 40b of the cutting means fastening device 10b is made. The bearing element 60b is made of a material, in particular a non-ferrous metal, preferably brass, which is different from the material from which the stop element 40b of the cutting means fastening device 10b is made. The fastening element 52b has the stop element 40b. The stop element 40b is formed by the fastening element 52b. The fastening element 52b is designed here, for example, as a screw. The fastening element 52b, in particular the stop element 40b, is made, for example, of steel or iron. Alternatively, however, it is also conceivable for the bearing unit 16b and the stop element 40b to be made of the same material.

[0052] At least a portion of the bearing unit 16b, in particular the bearing element 60b, is screwed onto the stop element 40b. The bearing unit 16b, in particular the bearing element 60b, has a thread. The portion of the bearing unit 16b, in particular the bearing element 60b, can be screwed onto the stop element 40b through the thread of the fastening element 52b. The thread of the bearing element 60b is provided for attachment to the stop element 40b, in particular to the fastening element 52b, for cooperation with the thread of the fastening element 52b. The circular-cylindrical bearing surface portion 58b is arranged, viewed in the axial direction 24b, between the angled bearing surface portion 26b and a stop surface 44b of the stop element 40b. An end of the angled bearing surface portion 36b remote from the stop surface 44b, in particular viewed parallel to the rotation axis 20b, delimits the bearing surface 22b at one end.An end of the circular cylindrical bearing surface portion 58b closest to the stop surface 44b, in particular viewed parallel to the rotational axis 20b, delimits the bearing surface 22b at a further end.

[0053] Fig. 5 shows a portion of a cutting device 12c with a cutting means fastening device 10c and with a cutting element 18c. The cutting means fastening device 10c has a bearing unit 16c for rotatably supporting the cutting element 18c about a rotation axis 20c.

[0054] The bearing unit 16c has a bearing surface 22c. The bearing surface 22c has a bearing surface portion 26c angled in the axial direction 24c relative to the rotation axis 20c.

[0055] A ratio of a maximum longitudinal extent 32c of the angled bearing surface portion 26c parallel to the rotation axis 20c to a maximum longitudinal extent 30c of the bearing surface 22c parallel to the rotation axis 20c is at least 0.30.

[0056] The cutting means fastening device 10c has a fastening element 52c. The bearing unit 16c is formed by the fastening element 52c. The stop element 40c is formed by the fastening element 52c. The fastening element 52c is attached directly to a knife disk 42c of the cutting device 12c.

[0057] The bearing surface 22c has a circular cylindrical bearing surface portion 58c. The circular cylindrical bearing surface portion 58c is arranged between the angled bearing surface portion 26c and the stop surface 44c, viewed in the axial direction 24c. The bearing surface 22c is composed of the angled bearing surface portion 26c and the circular cylindrical bearing surface portion 58c.

[0058] Fig. 6 shows a portion of a cutting device 12d with a cutting means fastening device 10d and with a cutting element 18d. The cutting means fastening device 10d has a bearing unit 16d for rotatably supporting the cutting element 18d about a rotation axis 20d.

[0059] The bearing unit 16d has a bearing surface 22d. The bearing surface 22d has a bearing surface portion 26d angled in the axial direction 24d relative to the rotation axis 20d. The ratio of a maximum longitudinal extension 32d of the angled bearing surface portion 26d parallel to the rotation axis 20d to a maximum longitudinal extension 30d of the bearing surface 22d parallel to the rotation axis 20d is at least 0.30.

[0060] A fixed position is arranged in the axial direction 24d at a distance from ends 28d, 38d of the bearing surface 22d. The fixed position of the cutting element 18d is defined independently of a stop element 40d of the cutting means fastening device 10d. In the fixed position, the cutting element 18d is spaced from the stop element 40d and in particular from a stop surface 44d of the stop element 40d. The fixed position is defined solely by a profile of the angled bearing surface portion 26d. In the fixed position in the at least one drive state, the cutting element 18d has two contact points 34d with the angled bearing surface portion 26d. The bearing surface 22d forms a concave shape, in particular a C-shape. The bearing surface 22d is formed entirely by the angled bearing surface portion 26d. The angled bearing surface portion 26d has a curved profile.

[0061] The cutting means fastening device 10d has a fastening element 52d. The stop element 40d and the bearing unit 16d are formed by the fastening element 52d.

[0062] Fig. Figure 7 shows a portion of a cutting device 12e with a cutting means fastening device 10e and a cutting element 18e. The cutting means fastening device 10e has a bearing unit 16e for rotatably supporting the cutting element 18e about a rotation axis 20e.

[0063] The bearing unit 16e has a bearing surface 22e. The bearing surface 22e has a bearing surface portion 26e angled in the axial direction 24e relative to the rotation axis 20e.

[0064] A ratio of a maximum longitudinal extension 32e of the angled bearing surface portion 26e parallel to the rotation axis 20e to a maximum longitudinal extension 30e of the bearing surface 22e parallel to the rotation axis 20e is at least 0.30.

[0065] The bearing surface 22e forms a wedge shape. The bearing surface 22e is completely formed by the angled bearing surface portion 26e. The angled bearing surface portion 26e consists of two straight bearing surface sections that extend at an angle to each other. In a fixed position, the cutting element 18e has two contact points 34e with the angled bearing surface portion 26e.

[0066] The cutting means fastening device 10e has a fastening element 52e. The stop element 40e and the bearing unit 16e are formed by the fastening element 52e.

Claims

[1] Cutting means fastening device (10a - 10e) for a cutting device (12a - 12e), in particular for a lawnmower (14a), preferably for an autonomous lawnmower, with a bearing unit (16a - 16e) for rotatably supporting a cutting element (18a - 18e) of the cutting device (12a - 12e) about a rotation axis (20a - 20e), wherein a bearing surface (22a - 22e) of the bearing unit (16a - 16e) has a bearing surface portion (26a - 26e) angled in the axial direction (24a - 24e) relative to the rotation axis (20a - 20e), characterized by that a ratio of a maximum longitudinal extent (32a - 32e) of the angled bearing surface portion (26a - 26e) parallel to the rotation axis (20a - 20e) to a maximum longitudinal extent (30a - 30e) of the bearing surface (22a - 22e) parallel to the rotation axis (20a - 20e) is at least 0.

30. [2] Cutting means fastening device (10a - 10e) according to claim 1, characterized bythat the bearing unit (16a - 16e), in particular by means of the angled bearing surface portion (26a - 26e), is provided to move the cutting element (18a - 18e) in at least one drive state with a force acting axially with respect to the axis of rotation (20a - 20e) in the direction of a fixed position, wherein the cutting element (18a - 18e) in the fixed position has at least one contact point (34a - 34e) with the angled bearing surface portion (26a - 26e). [3] Cutting means fastening device (10a - 10e) according to claim 1 or 2, characterized by that the angled bearing surface portion (26a) has an angle (36a) of at least 20° and at most 60° to the axis of rotation (20a). [4] Cutting means fastening device (10d; 10e) according to one of the preceding claims, characterized by that the bearing surface (22d; 22e) forms a wedge shape or a concave shape, in particular a C-shape or a U-shape. [5] Cutting means fastening device (10d; 10e) according to claim 2, characterized by that the fixed position is arranged in the axial direction (24d; 24e) at a distance from at least one end (28d; 28e), preferably from ends (28d, 38d; 28e, 38e), of the bearing surface (22d; 22e). [6] Cutting means fastening device (10a - 10c) according to claim 2, characterized by a stop element (40a - 40c) against which the cutting element (18a - 18c) rests in the fixed position, in particular flatly, wherein the cutting element (18a - 18c) in the fixed position in the at least one drive state is subjected to the axially acting force in the direction of the stop element (40a - 40c). [7] Cutting means fastening device (10b) according to claim 6, characterized bythat at least a part of the bearing unit (16b) is formed from a material, in particular from a non-ferrous metal, preferably brass, which is different from a material from which the stop element (40b) is formed. [8] Cutting means fastening device (10b) according to claim 6 or 7, characterized by that at least a part of the bearing unit (16b) is screwed onto the stop element (40b). [9] Cutting device (12a - 12e) with at least one cutting means fastening device (10a - 10e) according to one of the preceding claims and with at least one cutting element (18a - 18e). [10] Cutting device (12a - 12e) according to claim 9, characterized bya knife disc (42a - 42e) to which the cutting element (18a - 18e) can be fastened by means of the cutting means fastening device (10a - 10e), wherein a stop surface (44a - 44e) of the cutting means fastening device (10a - 10e), in particular running at least substantially perpendicular to the axis of rotation (20a - 20e), is arranged on an end (38a - 38e) of the bearing surface (22a - 22e) remote from the knife disc (42a - 42e). [11] Cutting device (12a - 12e) according to claim 10, characterized by that a minimum diameter (46a) of a fixing recess (48a) of the cutting element (18a) is smaller than a maximum extension (50a) of the stop surface (44a). [12] Lawnmower (14a), in particular autonomous lawnmower, with a cutting device (12a - 12e) according to one of claims 9 to 11.

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