阅读说明：本技术 用于机动镰刀的切割头 (Cutting head for motorized sickle ) 是由 A·雷塔贝尔 于 2021-06-15 设计创作，主要内容包括：本发明涉及一种用于机动镰刀的切割头,其中切割头包括带有上基体件(12)和下基体件(13)的分开的基体(11)。在下基体件(13)处布置有螺旋元件(19)。螺旋元件(19)用于机动镰刀在驱动轴(18)处的固定。在上基体件(12)和下基体件(13)之间设置至少一个容纳部(15)用于固定切割工具(14)。基体(11)在机动镰刀的运行中绕其转动轴线(17)可转动驱动。上基体件(12)和下基体件(13)借助于可松开的搭扣连接(1)彼此保持。(The invention relates to a cutting head for a motorized sickle, wherein the cutting head comprises a separate base body (11) with an upper base body member (12) and a lower base body member (13). A spiral element (19) is arranged at the lower base member (13). The screw element (19) is used for fixing the motorized sickle on the drive shaft (18). At least one receptacle (15) for holding a cutting tool (14) is provided between the upper base element (12) and the lower base element (13). The basic body (11) is rotatably driven about its axis of rotation (17) during operation of the motorized sickle. The upper base member (12) and the lower base member (13) are held to each other by means of a releasable snap connection (1).)

1. A cutting head for a motorized sickle is provided,

comprising a divided base body (11) with an upper base body part (12) and a lower base body part (13),

wherein a screw element (19) is arranged at the lower base member (13), wherein the screw element (19) is used for the fixation of a motorized sickle at a drive shaft (18),

wherein at least one receptacle (15) for fixing a cutting tool (14) is provided between the upper base element (12) and the lower base element (13),

wherein the base body (11) is rotatably driven about its axis of rotation (17) during operation of the motorized sickle,

wherein the upper base member (12) and the lower base member (13) are held to each other by means of a releasable snap connection (1), characterized in that the snap connection (1) has a distance (a) measured in radial direction with respect to the axis of rotation (17) of at most 40% of the diameter (d) of the cutting head (10).

2. The cutting head according to claim 1, characterized in that the snap connection (1) has a distance (a) measured in a radial direction with respect to the axis of rotation (17) of at most 30% of the diameter (d) of the cutting head (10).

3. The cutting head according to claim 2, characterized in that the receptacle (15) has a bearing shaft (32) extending in the direction of the axis of rotation (17), wherein the bearing shaft (32) has a distance (f) relative to the axis of rotation (17) and the distance (f) between the bearing shaft (32) and the axis of rotation (17) is greater than the distance (a) between the snap connection (1) and the axis of rotation (17).

4. The cutting head according to claim 1, characterized in that the snap connection (1) comprises at least one grapple (2) and at least one retaining profile (4) in operative connection with the grapple (2).

5. A cutting head according to claim 4, characterized in that the grapple (2) is arranged at the upper base member (12) and the at least one retaining profile (4) is arranged at the lower base member (13).

6. The cutting head according to claim 4, characterized in that the at least one grapple (2) has a hook head (3) configured for grasping the at least one holding profile (4) from the rear.

7. The cutting head according to claim 6, characterized in that the hook head (3) is configured such that the snap connection (1) latches when the base members (12,13) are pressed together and unlocks when the base members (12,13) are pulled away from each other.

8. The cutting head according to claim 1, characterized in that an interference profile (40) is provided at one of the two base members (12,13) and a guide groove (41) extending in the direction of the axis of rotation (17) is provided at the other base member (12,13) co-acting with the interference profile (40) to align the upper base member (12) and the lower base member (13) with each other in the circumferential direction of the axis of rotation (17) by means of the interference profile (40) and the guide groove (41).

9. The cutting head according to claim 8, characterized in that the snap connection (1) is configured such that the snap connection (1) can be snapped on only when the upper base member (12) and the lower base member (13) are aligned with each other via the interference contour (40) and the guide groove (41).

10. The cutting head according to claim 8, characterized in that torque can be transmitted in the circumferential direction between the upper base member (12) and the lower base member (13) via the interference profile (40) and the guide groove (41).

11. The cutting head according to claim 1, characterized in that the receptacle (15) is configured as a bearing bolt (16) and by means of the bearing bolt (16) a cutting tool (14) can be arranged at the basic body (11).

12. The cutting head according to claim 1, characterized in that the bearing bolt (16) is fixed on one side at the upper base member (12) or the lower base member (13).

13. The cutting head according to claim 11, wherein the bearing bolts (16) are fixed at the upper base member (12).

14. The cutting head according to claim 1, characterized in that the helical element (19) is arranged anti-rotatably at the lower base member (13).

15. A cutting head according to claim 1, characterized in that a cutting tool (14) is swingably arranged at the at least one accommodation (15).

Technical Field

The present invention relates to cutting heads.

Background

Cutting heads for motorized sickles (Motorsense) are known, which consist of a base body comprising two base members. The base body is driven in rotation about a rotational axis during operation of the motorized sickle. At least one cutting tool is arranged between the base parts, wherein the bearing bolts are arranged in the base body, at which the cutting tool is held. For the assembly of the cutting head, the cutting tool is threaded (auff ä deln) onto the bearing bolts and subsequently the base member is fixed to the drive shaft (sometimes called the output shaft) of the motorized sickle. A disadvantage of such a cutting head is that assembly is made considerably more difficult by the number of individual parts.

Disclosure of Invention

The object of the invention is to improve a cutting head of this type in such a way that a simple assembly and disassembly of the cutting head and a simple fixing of the cutting head at the drive shaft of the motorized sickle are possible.

This object is achieved by a cutting head for a motorized sickle, comprising a separate base body with an upper base part and a lower base part, wherein a screw element (schraubel element) is arranged at the lower base part, wherein the screw element is used for fixing the motorized sickle at a drive shaft, wherein at least one receptacle is provided between the upper base part and the lower base part for fixing a cutting tool, wherein the base body is rotatably drivable about its axis of rotation during operation of the motorized sickle, wherein the upper base part and the lower base part are held to one another by means of a releasable snap connection, wherein the snap connection has a distance measured in a radial direction with respect to the axis of rotation which is at most 40% of the diameter of the cutting head.

The cutting head for a motorized sickle according to the invention comprises a separate base body. The substrate, in turn, includes an upper substrate member and a lower substrate member. The upper base element is the base element which rests with its upper side against the motorized sickle when the cutting head end side is fixed. The lower base member is the base member that faces the ground during normal operation of the motorized sickle when the cutting head is secured at the motorized sickle. The helical element is arranged at the lower base. The screw element serves for fixing the basic body on the drive shaft of the motorized sickle. At least one receptacle is provided between the upper and lower base members for holding a cutting tool. The cutting tool is arranged axially, i.e. in the direction of the axis of rotation of the basic body, between the upper basic body element and the lower basic body element. The basic body is rotatably driven about its axis of rotation during operation of the motorized sickle. The upper and lower base members are held to each other by means of a releasable snap connection.

The snap connection enables an operator of the motorized sickle to connect the upper and lower base members with the cutting tool held at the pocket. The upper and lower base members are thereby connected to each other and form a unit with the cutting tool, which can be screwed onto the drive shaft of the motorized sickle. The operator of the motorized sickle thus does not have to individually fit different cutting head pieces on the drive shaft. Accidental detachment of the cutting head pieces is avoided even upon disassembly of the cutting head, since they are held to each other by a snap connection.

It is advantageously provided that the snap connection has a distance, measured in the radial direction with respect to the axis of rotation, of at most 40%, in particular at most 30%, preferably at most 25%, of the diameter of the cutting head.

It is advantageously provided that the receptacle has a bearing shaft which extends in the direction of the axis of rotation, wherein the bearing shaft has a distance to the axis of rotation and the distance between the bearing shaft and the axis of rotation is greater than the distance between the snap connection and the axis of rotation. The snap connection is thereby arranged in an inner region of the cutting head and thus protected. By the arrangement of the snap connection very close to the axis of rotation, the snap connection does not limit the oscillating movement of the cutting tool. If the cutting tool strikes a fixed obstacle during operation, the cutting tool can be pivoted back away opposite the direction of rotation of the cutting head without striking the snap connection.

The snap connection preferably comprises at least one catch and in particular at least one retaining profile which is in operative connection with the catch. The grapple is preferably arranged at the upper base member and the at least one retaining profile is preferably arranged at the lower base member. The grapple contacts the retention profile when the upper and lower base members are joined and is here deflected radially relative to the axis of rotation. For this purpose, the catch is preferably configured to be flexible in the radial direction relative to the axis of rotation. The snap-fit grapple latches the retention profile from the rear if the upper and lower base members are pushed together sufficiently. The at least one grapple preferably has a hook head configured for grasping the at least one retention profile from the rear. If the snap connection is snapped on, the upper and lower base members are held together in the direction of the axis of rotation of the cutting head. The hook heads are preferably directed outwards, in the radial direction, away from the axis of rotation. The catch hook is thereby pressed outward against the retaining contour by centrifugal force during operation of the motorized sickle. Thereby, the shape of the grapple or the pretensioning of the grapple against the retaining profile is also maintained over a long running duration of the cutting head.

The hook heads are preferably configured such that the snap connection latches when the upper and lower base members are pressed together and unlocks when the base members are pulled away from each other. For snap-on latching, the base members are pushed together in the direction of the axis of rotation, and for releasing the snap-on connection, the base members are pulled away from each other in opposite directions. The forces necessary for latching and releasing the snap connection result from the geometry of the hook head and the retaining contour. The spring action of the catch also influences the latching and releasing forces of the snap connection. By matching the geometry of the hook head and the retaining profile, the latching and unlatching forces of the snap connection can be correspondingly matched to the requirements at the cutting head. The snap connection has preferably 2, in particular 3 or more catches with corresponding retaining profiles. If a plurality of grapples and holding profiles are provided, they are preferably arranged at equal angular intervals around the axis of rotation of the cutting head.

Preferably, an interference contour is provided at one of the two base members and a guide groove extending in the direction of the axis of rotation is provided at the other base member, cooperating with the interference contour, to align the upper and lower base members with each other in the circumferential direction of the axis of rotation by means of the interference contour and the guide groove. The joining of the base members and thus the snap-connection latching is only possible if the upper and lower base members are aligned with one another in such a way that the interference contour can engage into the guide groove. Otherwise, the bonding of the base member is locked by the interference profile. The snap connection is thus in particular configured such that it can be latched only when the upper and lower base elements are aligned with one another via the interference contour and the guide groove. This enables the operator of the motorized sickle to correctly assemble the cutting head in a simple manner. Errors in the assembly of the cutting head are ruled out by the user in the sense of the error proofing law (Poka Yoke).

It is advantageously provided that torque can be transmitted in the circumferential direction between the upper and lower base elements via the interference contour and the guide groove. Thereby, the snap connection is already protected when torque is applied to the base member when the cutting head is assembled, since it is intercepted via the interference profile and the guide groove. The snap connection does not load torque. Preferably, the base body comprises at least two or also more interference profiles with corresponding guide grooves.

The receptacle for the cutting tool of the cutting head is preferably configured as a bearing bolt. The bearing bolt cutting tool can preferably be arranged on the base body. The bearing bolt is designed such that the cutting tool is held pivotably on the bearing bolt. The bearing bolts are preferably fixed on one side at the upper or lower base member. In this way, in particular with respect to the cutting head, the base parts thereof can also be screwed to one another via the bearing bolts, the assembly or disassembly of the base parts being possible in a simple manner. To separate or join the upper and lower base members, only the snap-fit connection should be released or latched. The bearing bolts are preferably fixed at the upper base member.

It is advantageously provided that the helical element is arranged in a rotationally fixed manner at the lower base part. When the cutting head is fixed at the motorized sickle, the cutting head is preferably screwed onto the drive shaft of the motorized sickle via a screw element as a preassembled unit. The lower base part is in this case tensioned via a screw element against the upper base part, wherein the upper base part is supported at the end face on the motorized sickle. The screw element may be an element separately constructed from the lower base or a thread provided in the lower base. Thereby ensuring that the helical element is again tensioned against the upper base member on the drive shaft by the lower base member.

The cutting tool is preferably arranged pivotably at least one receptacle of the cutting head. Grass, shrubs or the like can be cut with the outer section of the cutting tool protruding from the base of the cutting head.

Drawings

Further features of the invention emerge from the description and the drawing, in which the embodiments of the invention described in detail below are shown. Here:

figure 1 shows a motorized sickle with a cutting head in a schematic side view,

figure 2 shows a cutting head according to the invention with a cutting tool in a perspective view,

figure 3 shows the cutting head according to figure 2 in a side view,

figure 4 shows the cutting head according to figure 2 in a bottom view,

figure 5 shows the cutting head according to figure 2 in a top view,

figure 6 shows in a sectional view the cutting head along arrow VI according to figure 5,

figure 7 shows in a sectional view the cutting head along the arrow VII according to figure 5,

figure 8 shows in a sectional view the cutting head along the arrow VIII according to figure 7,

figure 9 shows in a sectional view a cutting head along the arrow IX according to figure 5,

figure 10 shows the cutting head with the swung-out cutting tool according to figure 2 from above in a sectional view,

figure 11 shows the upper base member of the cutting head in a perspective view,

figure 12 shows the upper base member of the cutting head in a bottom view,

figure 13 shows in a cross-sectional view the upper base member along the arrow XIII according to figure 12,

figure 14 shows a lower base member of the cutting head in perspective view,

FIG. 15 shows a lower base member of the cutting head in a top view and

figure 16 shows the lower base member in cross-section along the arrow XVI according to figure 15.

Detailed Description

Fig. 1 shows a perspective side view of a work apparatus 100 of the motorized sickle construction type. The cutting head 10 is arranged at the lower first end 5 of the guide tube 6, on the upper second end 105 of which a drive motor 101 is held. The drive motor 101 drives a connecting shaft 107, which is advantageously configured as a flexible shaft 7 and follows the bending of the guide tube 6. In the region of the upper end section of the guide tube 6, an operating handle 103 is provided, which projects through the guide tube 6. Adjacent to the operating handle 103, a round handle 104 fixed at the guide tube 6 is fitted.

By bending the guide tube 6, the working position of the cutting head 10 relative to the ground is determined without the need for a bevel gear transmission. Alternatively, the cutting head 10 may also be driven via a bevel gear transmission. The cutting head 10 is expediently arranged as close as possible to the end 5 of the guide tube 6 and is advantageously provided with a wrap-around protection 106, in order to prevent grass from being wound into the drive train. Other arrangements of the drive motor 101, in particular at the lower end 105 of the guide tube 6, may also be expedient.

As shown in fig. 2 to 4, the cutting head 10 includes a base 11 formed from an upper base member 12 and a lower base member 13. If the cutting head 10 is fixed to the work implement 100, the cutting head abuts the upper base member 12 against the work implement 100. The lower base member 13 faces the ground 4 in the normal operating position of the work implement 100. At least one cutting tool 14 is held between the upper and lower base members 12, 13. A screw element is arranged on the base body 11 for fastening the cutting head 10 to the drive shaft 18 of the work apparatus 100 (fig. 4). The cutting head 10, in particular the main body 11, is driven in rotation about the axis of rotation 17 during operation of the work apparatus 100.

As shown in fig. 2 to 4, the cutting head 10 in the exemplary embodiment comprises two cutting tools 14, which are each held at a receptacle 15. The cutting tool 14 is in the preferred embodiment designed as a cutting tool. The cutting head 10 preferably has a further housing 45 for fixing the string. Thus, the cutting head 10 can be run with a cutting tool and/or with a cutting wire. The receptacle 15 is designed as a bearing bolt 16 (fig. 6), whereby the cutting tool 14 is held at the bearing bolt 16 so as to be pivotable about its bearing shaft 32. The bearing shaft 32 of the bearing bolt 16 extends parallel to the axis of rotation 17. Three or more cutting tools 14 may also be provided in alternative implementations of cutting head 10. In order to avoid an unbalance of cutting head 10, receptacles 15 for cutting tools 14 are arranged at a uniform angular distance β about axis of rotation 17 of cutting head 10. Thereby, the angular distance β between the bearing shafts 32 of adjacent receptacles 15 is preferably constant. Accordingly, the angular distance β is 180 ° in the present embodiment of a cutting head with two receptacles 15.

As shown in fig. 4 and 6, the spiral element 19 is arranged at the lower base member 13. The screw element 19 is configured in the exemplary embodiment as a nut. In the embodiment the spiral element 19 is arranged in the lower base member 13. The spiral element 19 is hexagonal in configuration and is accommodated in a corresponding mating contour of the lower base part 13, whereby it is held in a form-fitting manner against rotation relative to the base part 13. The screwing of the helical element 19 is ensured during operation of the cutting head 10 by the inertia of the lower base member 13. The spiral element 19 is constructed in an embodiment from a metallic material. The lower base member 13 is in turn made of plastic. The spiral element 19 is in the embodiment pressed into the lower base part 13, however as an alternative fixing at the lower base part 13 an injection moulding of plastic may be used. In an alternative embodiment of the cutting head 10, it may be expedient for the screw element 19 to be configured as a loss-proof nut which is rotatable relative to the lower base part. In the fixing of the cutting head 10, it is screwed onto a drive shaft 18, which is schematically illustrated in fig. 3, by means of a screw element 19.

The cutting head 10 is shown in top view in fig. 5 for the purpose of depicting different cross-sectional views.

The illustration according to fig. 6 shows a section of the cutting head 10 with the cutting tool 14 through a receptacle 15 configured as a bearing bolt 16. In a preferred implementation of the cutting head 10, the bearing bolts 16 are fixed at the upper base member 12. In an alternative embodiment, it may be expedient for the bearing bolts 16 to be fastened to the lower base element 13. The bearing bolts 16 are fixed to either the upper base member 12 or the lower base member 13 on one side. The bearing bolt 16 has a threaded section 20 and a retaining section 21. The bearing bolt 16 is screwed with its threaded section 20 into a retaining thread 22 provided at the upper base element 12. In an embodiment the retaining thread 22 is constructed by a nut that is injection molded around with plastic in the upper base member 12. Alternatively, retaining threads 22 may be pressed into upper base member 12. In an embodiment, the retaining thread 22 is knurled at the peripheral side for better force transmission. The upper base member 12 comprises an opening 23 which extends approximately coaxially with a bearing shaft 32 of the bearing bolt 16 up to an upper side 30 of the upper base member 12 facing the work implement 100. The openings 23 serve to prevent material from accumulating during the overmolding of the retaining thread 22 and to prevent the plastic from penetrating into the internal thread of the retaining thread 22. The bearing bolts 16 are screwed into the retaining thread 22 via a lower side 31 of the upper base element 12 facing away from the upper side 30. The upper and lower base members 12,13 are held together non-coaxially by bearing bolts 16.

The pulling away of the two base members 12,13 from each other does not require a change at the bearing bolts 16.

The independent inventive idea of the present cutting head 10 is that, as shown in fig. 6, a support plate 24 made of metal is provided, which is fixed at the lower side 31 of the upper base part 12 facing the lower base part 13. The support plate 24 is in the embodiment constructed in one piece and has a main opening to partially execute the lower base member 13. Furthermore, the support plate 24 has a further opening for each bearing bolt 16, through which the respective bearing bolt 16 extends. The support plates 24 are used to support the bearing bolts 16 against the upper base member 12. A support ring 25 is arranged between the first shoulder 38 of the bearing bolt 16 and the support plate 24. When the bearing bolt 16 is bolted via the retaining thread 22, the bearing bolt 16 is tensioned via the first shoulder 38 and the support ring 25 against the support plate 24. Forces are introduced into the upper base member 12 through the support plate 24. The high support force can be ensured by the support plate 24 being constructed from metal. Since all bearing bolts 16 are supported at the same support plate 24, a part of the forces occurring during operation can be compensated for one another. Thereby, the upper base member 12 is unloaded.

As shown in fig. 6, a bearing sleeve 26 is provided at the retaining section 21 of the bearing bolt 16, at which the cutting tool 14 is retained. Thereby, the cutting tool 14 can swing about the bearing shaft 32 of the bearing bolt 16. The bearing shaft 32 of the bearing bolt 16 extends parallel to the axis of rotation 17 of the cutting head 10. The bearing sleeve 26 is arranged floating between the support ring 25 and the second shoulder 39 of the bearing bolt 16. The bearing sleeve 26 is preferably oiled and constructed of a sintered metal, thereby reducing friction between the cutting tool 14 and the bearing bolt 16. Heat generated during oscillation between bearing sleeve 26 and cutting tool 14 is transferred to upper base member 12 via support plate 24.

The cutting tool 14 is held pivotably at one end thereof in a pivot gap 28 of the cutting head 10 at the bearing sleeve 26 and projects with the other end from the pivot gap 28. The swing gap 28 is limited by the underside 31 of the upper base member 12 and by the upper side 43 of the lower base member 13 facing the underside 31. If the cutting head 10 is assembled, the bearing bolt 16 extends via the entire height of the pivot gap 28 extending in the direction of the axis of rotation 17 and projects into a bolt opening 27 of the lower base part 13 provided for the bearing bolt 16. The bearing bolts 16 sinking into the bolt openings 27 are also supported by the lower base member 13.

As shown in fig. 6, upper base member 12 has a through hole 46 extending coaxially with respect to rotational axis 17 for the insertion of a plug through drive shaft 18. In embodiments of the cutting head 10 no form fit is provided between the drive shaft 18 and the upper base member 12. In an alternative embodiment, a form fit may also be provided between drive shaft 18 and upper base member 12. In such an embodiment, the snap connection 1 is however configured to be rotatable at the retaining profile 4, so that the lower base element 13 can be rotated onto the drive shaft 18. If the screw element 19 is merely configured to be rotatable relative to the lower base member 13, the rotatable snap connection 1 can be dispensed with.

The lower base member 13 is divided into an inner zone 33 and an outer zone 34 in a radial direction towards the axis of rotation 17. The inner region 33 of the lower base member 13 is configured as a dome 35 that extends into a central opening 36 of the upper base member 12. The central opening 36 is in particular of pot-shaped design and extends around the through-opening 46. In the assembled state of the cutting head 10, the dome 35 contacts with its end side 47 facing the lower side 31 of the upper base member 12 at the end side 50 of the central opening 36. The end side 47 is part of the upper side 43 of the lower base member 13. The outer region 34 of the lower base member 13 is essentially used for the formation of the cutting tool 14 between the upper base member 12 and the lower base member 13 at the fixed and swing gap 28 of the pocket 15. In a preferred embodiment, the dome 35 of the lower base element 13 has a diameter e measured radially with respect to the axis of rotation 17, which corresponds in particular to at most 50% of the diameter d of the cutting head 10 measured radially with respect to the axis of rotation 17. In an alternative implementation of the cutting head 10, a dome with a larger diameter e may also be suitable. The spiral element 19 is held, in particular anti-rotation, in the dome 35 of the lower base member 13.

As shown in fig. 7, 8, 13, 16, cutting head 10 includes a releasable snap connection 1. The snap connection 1 comprises at least one catch 2 and at least one retaining profile 4. The grapple 2 is preferably constructed to be bendable in a radial direction away from the axis of rotation 17. The at least one grapple 2 is configured at the upper base member 12 and extends into the central opening 36 of the upper base member 12. At the end of the grapple 2 facing the lower base part 13, a hook head 3 is formed. The retaining profile 4 is configured at the lower base member 13, in particular at the domes 35 of the lower base member 13. The snap connection 1 is constructed between the mutually facing end sides 47, 50 of the base members 12,13, i.e. the lower side 31 of the upper base member 12 and the upper side 43 of the lower base member 13. The grapple 2 is protectively arranged in a pot-shaped central opening 36 of the upper base element 12.

When the cutting head 10 is assembled, the upper base member 12 and the lower base member 13 are pushed together in such a way that the grapple 2 penetrates into the holding opening 8 at the dome 35 and the grapple 2 and the holding profile 4 are in active connection. In this case, the catch hook 2 latches into the retaining contour 4. The catch hook 2 grips the retaining profile 4 with its hook head 3 from the rear, whereby the snap connection 1 latches. The upper base member 12 and the lower base member 13 are connected by means of a snap connection 1. The snap connection 1 in the latched position generates a retaining force between the upper base element 12 and the lower base element 13, which acts substantially in the direction of the axis of rotation 17.

To release the snap connection 1 again, the upper base member 12 and the lower base member 13 are pulled away from each other in the direction of the axis of rotation 17. In this case, only the holding force of the snap connection 1 has to be overcome. The retaining head 3 has a contact surface 9 which produces an effective connection with the retaining contour 4. The contact surface 9 is oriented obliquely to the axis of rotation 17, i.e. with respect to the pulling direction of the upper and lower base members 12, 13. If the operator pulls the base elements 12,13 away from each other with sufficient pulling force, the hook head 3 slides away via its inclined contact surface 9 at the retaining profile 4, whereby the grapple 2 is pressed inwards towards the axis of rotation 17. Here, the snap connection 1 is released and the base parts 12,13 are separated from each other.

As shown in fig. 7 and 8, the snap connection 1 of the preferred embodiment comprises two grapples 2 with corresponding retaining profiles 4. In alternative embodiments, it may be expedient to also provide a plurality of hooks 2 with a plurality of retaining contours 4. If the snap connection 1 comprises a plurality of grapples 2, said grapples are preferably distributed with a uniform angular spacing in the circumferential direction of the axis of rotation 17. The retention of the snap connection 1 can be improved by using a plurality of grapples 2. Alternatively, the contact surface 9 of the hook head 3 and the retaining profile 4 in operative connection therewith can also be matched to set the retaining force to be achieved.

The fixation of the cutting head 10 takes place in the following steps:

the operator rotates the work implement 100 such that the end of the drive shaft 18 is directed against gravity. The upper base member 12 is then threaded onto the drive shaft 18. The operator then threads the cutting tool 14 onto the bearing bolt 16, which is tightened at the upper base member 12. The operator pushes the lower base member 13 onto the upper base member 12 until the snap connection 1 snaps. The entire cutting head 10 is then screwed onto the drive shaft 18 via the screw element 19 at the lower base part 13. Alternatively, the base members 12,13 can be preassembled with the cutting tool 14 and then screwed onto the drive shaft 18.

The snap connection 1 enables an operator to pre-assemble the base members 12,13 with the cutting tool 14 and to bolt the assembly consisting of the cutting head 10 and the cutting tool 14 together at the drive shaft 18 of the work apparatus 100. Thereby avoiding the operator from losing a single part while securing the cutting head 10. Thereby simplifying assembly of the cutting head 10.

As shown in fig. 8 and 9, cutting head 10 includes an interference profile 40 and a guide slot 41. In an embodiment interference profile 40 is configured at upper base member 12. And the guide groove 41 is configured at the lower base member 13. In an alternative embodiment of the cutting head 10, it is obvious that the interference contour 40 can also be constructed at the lower base part 13 and the guide groove 41 at the upper base part 12. As shown in particular in fig. 11 and 12, the interference contour 40 is formed at the inner wall 37 of the upper base element 12. The interference contour 40 is configured as a rib 42 which extends in the axial direction, i.e. in the direction of the axis of rotation 17. To avoid material accumulation for production engineering reasons, a recess is provided in the middle of the rib 42. Ribs 42 project from inner wall 37 of upper base member 12 into central opening 36. In the exemplary embodiment, two interference contours 40 are provided, which have the same angular distance to one another in the circumferential direction relative to the axis of rotation 17.

In fig. 14 and 15, a guide groove 41 is shown, which is configured at the dome 35 of the lower base member 13. The guide groove 41 extends from the end side of the dome 35 away from the end side of the dome 35 toward the direction of the rotation axis 17. In the present exemplary embodiment, two guide grooves 41 are provided, which, like the interference contour 40, are arranged at equal angular distances in the circumferential direction with respect to the rotational axis 17. The number of guide slots 41 at the dome 35 corresponds to the number of interference profiles 40 at the inner wall 37 of the upper base member 12 in the embodiment. It can also be provided that there are fewer interference profiles 40 than guide grooves 41.

When the cutting head 10 is assembled, the interference profile 40 and the guide groove 41 interact to ensure that the upper and lower base members 12,13 can only be assembled with each other in a predetermined position. For assembly, the base members 12,13 must therefore be aligned with one another in the circumferential direction. The upper base element 12 slides with its interference contour 40 along the end face 47 of the dome 35 until the operator, by rotating, aligns the base elements 12,13 with one another in such a way that the interference contour 40 and the guide groove 41 are situated opposite one another in the direction of the axis of rotation 17. The upper base member 12 has a flange 48 with a flange end side 49 protruding in the axial direction via the interference element 40, which reduces the radial alignment of the two base members 12,13 with respect to each other during rotation by the operator. The interference contour 40 is designed such that it can be slid into the guide groove 41 and the base parts 12,13 can be pushed together.

The snap connection 1 and the interference contour 40 or the guide groove 41 are coordinated with one another in such a way that, when the base part 12 is pushed together, firstly, the interference contour 40 must slide into the guide groove 41 before the catch hook 2 can be inserted into the retaining opening 8. By means of the contact between the interference contour 40 and the guide groove 41, a torque between the base members 12,13 can be transmitted in the circumferential direction relative to the axis of rotation 17. This results in that the base elements 12,13 can no longer rotate relative to one another already when the catch hook 2 penetrates into the retaining opening 3 at the dome 35. The base elements 12,13 are connected to one another in a rotationally fixed manner by the interaction of the interference contour 40 and the guide groove 41. The interference contour 40 and the guide groove 41 form a form-fit connection in the circumferential direction relative to the axis of rotation 17. Thereby, unintentional rotation of the base members 12,13 by an operator is avoided. The grapple 2 is thus prevented from breaking off during the assembly process of the cutting head 10. The catch hook 2 of the snap connection 1 is protected during assembly by the interference contour 40 and the guide groove 41.

As shown in fig. 9, the thread of the screw element 19 has a thread length g measured in the direction of the axis of rotation 17. The upper base member 12 has a total plunge depth h measured axially, which corresponds to the distance between the flange end side 49 of the flange 48 and the end side 50 of the central opening 36. The interference profile 40 has a length i measured axially from an end side 50 of the central opening 36 to an end side of the interference profile 40. Furthermore, the catch hook 2 has a penetration depth j, which extends axially measured from the end face 50 of the central opening 36 to the end of the hook head 3. The total immersion depth h is greater than the length i of the interference contour 40, so that during the assembly of the base parts 12,13, it is first guided radially by the flange 48. The length i of the interference contour 40 is greater than the depth of penetration j of the catch 2, so that the interference contour 40 engages first with the guide groove 41 and only then does the catch 2 engage into the retaining contour 4. The length i of the interference contour 40 is at least 120%, in particular 150%, preferably approximately 200%, of the penetration depth j of the catch 2. The interference profile j preferably corresponds substantially to the thread length g of the screw element 19.

As shown in fig. 12, the interference contour 40 is located at half the angular distance between adjacent bolt bearings 16, here 90 °. This is advantageous because the guide groove 41 forms part of the string accommodation. The grapple 2 is preferably arranged intermediately between the bearing bolt 16 and the interference profile 40 adjacent to each other. The grapple 2 can also be arranged eccentrically between the bearing bolt 16 and the interference profile 40, depending on the structure of the base elements 12,13 and the respective reinforcing ribs.

In fig. 10, a sectional view of cutting head 10 is shown, in which cutting tool 14 is maximally swung out. The pivot angle α is produced by two opposing pivot stops for the base body 11 of the respective cutting tool 14. Fig. 10 shows the maximum pivot angle α of the cutting tool 14, measured in the circumferential direction relative to the bearing bolt 16, starting from the long axis 29 of the cutting tool 14. The pivot angle α is preferably at least 60 °, preferably at least 120 °, in particular approximately 200 °. The plane of oscillation of the cutting tool 14 is arranged perpendicular to the axis of rotation 17. As shown in fig. 7, the snap connection 1 has a distance a, measured in the radial direction with respect to the axis of rotation 17, of at most 40%, preferably at most 30%, in particular 25%, of the diameter d of the cutting head 10. The bearing shaft 32 has a distance f relative to the axis of rotation 17. The distance f between the bearing shaft 32 and the axis of rotation 17 is greater than the distance a between the snap connection 1 and the axis of rotation 17 (see fig. 12). The snap connection 1 is thus located inside the bearing shaft 32 of the bearing bolt 16 in the radial direction with respect to the axis of rotation 17. By constructing the snap connection 1 in the vicinity of the axis of rotation 17, the structural element is displaced into the interior region of the cutting head 10. Thereby, the wobble gap 28 may accordingly remain free and a larger tilt angle β may be achieved. Furthermore, the cutting tool 14 has a length b measured in its longitudinal direction, wherein the length b corresponds to at least 60% of the diameter d of the cutting head 10. In an alternative embodiment of the cutting head 10, the length b of the cutting tool 14 can also be configured to be shorter.