Cutting head for motorized sickles

Abstract

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 part (12) and a lower base body part (13). A screw element (19) is arranged on the lower base body part (13). The screw element (19) is used to fix the motorized sickle on a drive shaft (18). At least one receiving portion (15) is arranged between the upper base body part (12) and the lower base body part (13) for fixing a cutting tool (14). The base body (11) can be driven to rotate around its rotation axis (17) during the operation of the motorized sickle. The upper base body part (12) and the lower base body part (13) are held together by means of a releasable snap connection (1).

Description

Technical Field

[0001] The invention relates to a cutting head. Background Art

[0002] A cutting head for a motorized sickle is known, which consists of a base body, wherein the base body comprises two base parts. The base body is driven in rotation about an axis of rotation during operation of the motorized sickle. At least one cutting tool is arranged between the base parts, wherein a bearing bolt is arranged in the base body, on which the cutting tool is held. For assembly of the cutting head, the cutting tool is threaded onto the bearing bolt and then the base part is fastened to the drive shaft (Abtriebswelle, sometimes called output shaft) of the motorized sickle. A disadvantage of such a cutting head is that the assembly is significantly complicated by the large number of individual parts. Summary of the invention

[0003] The object of the present invention is to improve a cutting head of the generic type in such a way that a simple assembly and disassembly of the cutting head and a simple fastening of the cutting head to the drive shaft of a motorized sickle are possible.

[0004] This object is achieved by a cutting head for a motor sickle, comprising a separate base body with an upper base part and a lower base part, wherein a screw element is arranged on the lower base part, wherein the screw element is used to fix the motor sickle to the drive shaft, wherein at least one receptacle is provided between the upper base part and the lower base part for fixing the cutting tool, wherein the base body can be driven rotationally about its rotation axis during operation of the motor sickle, wherein the upper base part and the lower base part are held to each other by means of a releasable snap connection, wherein the snap connection has a distance measured in a radial direction relative to the rotation axis, which is at most 40% of the diameter of the cutting head.

[0005] The cutting head for a motorized sickle according to the present invention comprises a separate base body. The base body then comprises an upper base body part and a lower base body part. The upper base body part is the base body part that is abutted against the motorized sickle with its upper side when the cutting head end side is fixed. The lower base body part is the base body part that faces the ground during normal operation of the motorized sickle when the cutting head is fixed to the motorized sickle. The spiral element is arranged at the lower base body. The spiral element is used to fix the base body at the drive shaft of the motorized sickle. At least one accommodating portion is provided between the upper base body part and the lower base body part for fixing the cutting tool. The cutting tool is arranged axially, that is, in the direction of the rotation axis of the base body, between the upper base body part and the lower base body part. The base body can be driven rotatably around its rotation axis during the operation of the motorized sickle. The upper base body part and the lower base body part are held to each other by means of a releasable snap connection.

[0006] The snap-on connection enables the operator of the motorized sickle to connect the upper base part and the lower base part, wherein the cutting tool is held in the receptacle. The upper base part and the lower base part are thus connected to one another and form a unit with the cutting tool, which can be screwed onto the drive shaft of the motorized sickle. As a result, the operator of the motorized sickle does not have to individually assemble different cutting head parts on the drive shaft. Even when the cutting head is disassembled, an accidental fall-off of the cutting head parts is avoided, because they are held together by the snap-on connection.

[0007] It is advantageously provided that the snap-fit ​​connection has a distance, measured in the radial direction relative to the axis of rotation, which is at most 40%, in particular at most 30%, preferably at most 25% of the cutting head diameter.

[0008] Advantageously, it is provided that the receiving portion has a bearing shaft extending in the direction of the axis of rotation, wherein the bearing shaft has a distance relative 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-on connection and the axis of rotation. As a result, the snap-on connection is arranged in the inner area of ​​the cutting head and is thus protected. Due to the very close arrangement of the snap-on connection to the axis of rotation, the snap-on connection does not restrict the swinging movement of the cutting tool. If the cutting tool hits a fixed obstacle during operation, the cutting tool can swing back away in the opposite direction of the rotation direction of the cutting head without hitting the snap-on connection.

[0009] The snap-on connection preferably comprises at least one catch hook and in particular at least one retaining profile which is in effective connection with the catch hook. The catch hook is preferably arranged at the upper base part, and the at least one retaining profile is preferably arranged at the lower base part. When the upper base part and the lower base part are joined, the catch hook contacts the retaining profile and deflects radially relative to the axis of rotation. For this purpose, the catch hook is preferably configured to be bendable in the radial direction relative to the axis of rotation. If the upper base part and the lower base part are pushed together sufficiently, the catch hook of the snap-on connection latches the retaining profile from the rear. The at least one catch hook preferably has a hook head which is configured to grip the at least one retaining profile from the rear. If the snap-on connection is latched, the upper base part and the lower base part are held together in the direction of the axis of rotation of the cutting head. The hook head preferably points outwards, away from the axis of rotation in the radial direction. As a result, the catch hook is pressed outwards against the retaining profile by centrifugal force during the operation of the motorized sickle. As a result, the shape of the catch hook or the pretension of the catch hook against the retaining profile is also maintained over a long operating duration of the cutting head.

[0010] The hook head is preferably designed in such a way that the snap-on connection is locked when the upper base part and the lower base part are pressed together and unlocked when the base parts are pulled away from each other. For locking the snap-on connection, the base parts are pushed together in the direction of the rotation axis, and for releasing the snap-on connection, the base parts are pulled away from each other in the opposite direction. The forces necessary for locking and releasing the snap-on connection are derived from the geometry of the hook head and the retaining profile. The elastic effect of the catch hook also influences the locking and releasing forces of the snap-on connection. By matching the geometry of the hook head and the retaining profile, the locking and releasing forces of the snap-on connection can be correspondingly matched to the requirements at the cutting head. The snap-on connection has preferably two, in particular three or more, catch hooks with corresponding retaining profiles. If a plurality of catch hooks and retaining profiles are provided, they are preferably arranged at equal angular distances around the rotation axis of the cutting head.

[0011] Preferably, an interference contour is provided on one of the two base parts and a guide groove extending in the direction of the rotation axis and cooperating with the interference contour is provided on the other base part, so that the upper base part and the lower base part are aligned with each other in the circumferential direction of the rotation axis by means of the interference contour and the guide groove. The joining of the base parts and thus the locking of the snap connection are only possible when the upper base part and the lower base part are aligned with each other in such a way that the interference contour can engage in the guide groove. Otherwise, the joining of the base parts is locked by the interference contour. The snap connection is therefore particularly designed in such a way that the snap connection can only be locked when the upper base part and the lower base part are aligned with each other 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 during the assembly of the cutting head are eliminated by the user in the sense of the Poka Yoke method.

[0012] Advantageously, it is provided that torque can be transmitted in the circumferential direction between the upper base part and the lower base part via the interference contour and the guide groove. As a result, the snap-on connection is already protected when torque acts on the base part during assembly of the cutting head, because it is intercepted via the interference contour and the guide groove. The snap-on connection is not loaded with torque. Preferably, the base body comprises at least two or more interference contours with corresponding guide grooves.

[0013] The receiving portion for the cutting tool of the cutting head is preferably configured as a bearing bolt. The cutting tool can preferably be arranged at the base body by means of the bearing bolt. Here, the bearing bolt is configured so that the cutting tool can be held pivotably at the bearing bolt. The bearing bolt is preferably fixed on one side to the upper base part or the lower base part. As a result, in particular with respect to the cutting head, its base parts can also be screwed to each other via the bearing bolt, and the assembly or disassembly of the base parts can be achieved in a simple manner. In order to separate or combine the upper base part and the lower base part, only the snap connection should be loosened or locked. The bearing bolt is preferably fixed to the upper base part.

[0014] Advantageously, the screw element is arranged on the lower base part in a rotationally fixed manner. When the cutting head is fixed to the motor sickle, the cutting head is preferably screwed onto the drive shaft of the motor sickle as a preassembled unit via the screw element. Here, the lower base part is tensioned against the upper base part via the screw element, wherein the upper base part is supported at the end side on the motor sickle. The screw element can be an element constructed separately from the lower base or a thread provided in the lower base. This ensures that the screw element is tensioned again against the upper base part on the drive shaft with the lower base part.

[0015] The cutting tool is preferably arranged pivotably on at least one receptacle of the cutting head. The outer section of the cutting tool that protrudes from the base body of the cutting head can be used to cut grass, bushes or the like. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Further features of the invention emerge from the description and the drawings, in which exemplary embodiments of the invention are shown, which are described in detail below.

[0017] Figure 1 A motorized sickle with a cutting head is shown in a schematic side view,

[0018] Figure 2 A cutting head according to the invention with a cutting tool is shown in a perspective view,

[0019] Figure 3 The side view shows the Figure 2 The cutting head

[0020] Figure 4 The bottom view shows the Figure 2 The cutting head

[0021] Figure 5 The top view shows the Figure 2 The cutting head

[0022] Figure 6 The cross-section diagram shows the Figure 5 The cutting head of arrow VI,

[0023] Figure 7 Display the cross-section along the Figure 5 The cutting head of arrow VII,

[0024] Figure 8 Display the cross-section along the Figure 7 The cutting head of the arrow VIII,

[0025] Fig. 9 Display the cross-section along the Figure 5 The cutting head of arrow IX,

[0026] Fig.10Shown from above in cross section with Figure 2 The cutting head of the swinging cutting tool,

[0027] Fig.11 The upper base part of the cutting head is shown in a perspective view,

[0028] Fig.12 The upper base member of the cutting head is shown in a bottom view,

[0029] Fig.13 The cross-sectional view shows the Fig.12 The upper base piece of arrow XIII,

[0030] Fig.14 The lower base part of the cutting head is shown in a perspective view,

[0031] Fig.15 The lower base part of the cutting head is shown in a top view and

[0032] Fig.16 The cross-sectional view shows the Fig.15 The arrow XVI is the lower base member. DETAILED DESCRIPTION

[0033] exist Figure 1 1 shows a work implement 100 of the motorized sickle type in a perspective side view. The cutting head 10 is arranged at the lower first end 5 of the guide tube 6, and a drive motor 101 is held at its upper second end 105. The drive motor 101 drives a connecting shaft 107, which is advantageously designed as a flexible shaft 7 and follows the curvature of the guide tube 6. An operating handle 103 is arranged in the region of the upper end section of the guide tube 6, which extends through the guide tube 6. A round handle 104 fixed to the guide tube 6 is mounted adjacent to the operating handle 103.

[0034] The working position of the cutting head 10 relative to the ground is determined by the curvature of the guide tube 6 without the need for a bevel gear transmission. Alternatively, the cutting head 10 can 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 winding protection 106 to prevent grass from being rolled 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.

[0035] As in Figures 2 to 4As shown in FIG. 1 , the cutting head 10 comprises a base body 11 which is formed by an upper base part 12 and a lower base part 13. If the cutting head 10 is fixed to the working device 100, it rests on the working device 100 with the upper base part 12. The lower base part 13 faces the ground 4 in the normal operating position of the working device 100. At least one cutting tool 14 is held between the upper base part 12 and the lower base part 13. In order to fix the cutting head 10 to the drive shaft 18 of the working device 100, a screw element ( Figure 4 The cutting head 10 , in particular the basic body 11 , is driven in rotation about the axis of rotation 17 during operation of the work tool 100 .

[0036] As in Figures 2 to 4 As shown in FIG. 1 , the cutting head 10 in the exemplary embodiment comprises two cutting tools 14, which are each held in a receptacle 15. The cutting tools 14 are designed as cutting knives in a preferred embodiment. The cutting head 10 preferably has a further receptacle 45 for fixing the cutting wire. Thus, the cutting head 10 can be operated with the cutting knives and / or with the cutting wire. The receptacle 15 is designed as a bearing bolt 16 ( Figure 6 ), whereby the cutting tool 14 is held pivotably about its bearing axis 32 at the bearing bolt 16. The bearing axis 32 of the bearing bolt 16 extends parallel to the axis of rotation 17. In an alternative embodiment of the cutting head 10, three or more cutting tools 14 can also be provided. In order to avoid an imbalance of the cutting head 10, the receptacles 15 for the cutting tools 14 are arranged around the axis of rotation 17 of the cutting head 10 at a consistent angular distance β. As a result, the angular distance β between the bearing axes 32 of adjacent receptacles 15 is preferably constant. Accordingly, in the current embodiment of a cutting head with two receptacles 15, the angular distance β is 180°.

[0037] As in Figure 4 and 6 As shown in , the screw element 19 is arranged at the lower base part 13. The screw element 19 is constructed as a nut in the embodiment. In the embodiment, the screw element 19 is arranged in the lower base part 13. The screw element 19 is constructed in a hexagonal shape and is accommodated in a corresponding matching contour of the lower base part 13, whereby it is held in a form-fitting manner to prevent rotation relative to the base part 13. The tightening of the screw element 19 is ensured by the inertia of the lower base part 13 during the operation of the cutting head 10. The screw element 19 is constructed of a metal material in the embodiment. The lower base part 13 is, on the other hand, made of plastic. The screw element 19 is pressed into the lower base part 13 in the embodiment, but as an alternative fixation at the lower base part 13, plastic surrounding injection molding can be used. In an alternative embodiment of the cutting head 10, it may be appropriate to construct the screw element 19 as a loss-proof nut, which is rotatable relative to the lower base part. In the fixation of the cutting head 10, it is screwed onto the lower base part 13 with the help of the screw element 19. Figure 3On the drive shaft 18 shown schematically in FIG.

[0038] exist Figure 5 1 and 2 show the cutting head 10 in a top view in order to illustrate different cross-sectional views.

[0039] according to Figure 6 The diagram of shows a section through a receiving portion 15 configured as a bearing bolt 16 of a cutting head 10 with a cutting tool 14. In a preferred embodiment of the cutting head 10, the bearing bolt 16 is fixed to the upper base part 12. In an alternative embodiment, it may be suitable that the bearing bolt 16 is fixed to the lower base part 13. The bearing bolt 16 is fixed on one side either to the upper base part 12 or to the lower base part 13. The bearing bolt 16 has a threaded section 20 and a retaining section 21. The bearing bolt 16 is screwed into a retaining thread 22 arranged at the upper base part 12 with its threaded section 20. In the embodiment, the retaining thread 22 is constructed by a nut that is injection molded with plastic in the upper base part 12. Alternatively, the retaining thread 22 can be pressed into the upper base part 12. In the embodiment, the retaining thread 22 is knurled at the peripheral side for better force transmission. The upper base part 12 comprises an opening 23, which extends approximately coaxially with the bearing axis 32 of the bearing pin 16 to the upper side 30 of the upper base part 12 facing the work tool 100. The opening 23 serves to avoid material accumulation during the surrounding injection molding of the retaining thread 22 and to prevent plastic from penetrating into the inner thread of the retaining thread 22. The bearing pin 16 is screwed into the retaining thread 22 via the lower side 31 of the upper base part 12 facing away from the upper side 30. The upper base part 12 and the lower base part 13 are held together non-coaxially by the bearing pin 16.

[0040] Pulling the two base parts 12 , 13 away from each other does not require any changes in the bearing bolt 16 .

[0041] The independent inventive concept of the present cutting head 10 is that, as in Figure 6As shown in FIG. 1 , a support plate 24 made of metal is provided, which is fixed to the lower side 31 of the upper base part 12 facing the lower base part 13. The support plate 24 is constructed in one piece in the embodiment and has a main opening to partially execute the lower base part 13. In addition, the support plate 24 has a further opening for each bearing bolt 16, through which the respective bearing bolt 16 extends. The support plate 24 is used to support the bearing bolt 16 against the upper base part 12. A support ring 25 is provided 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 against the support plate 24 via the first shoulder 38 and the support ring 25. Force is introduced into the upper base part 12 via the support plate 24. A high support force can be ensured by the support plate 24 being constructed of metal. Since all bearing bolts 16 are supported at the same support plate 24, a part of the forces occurring during operation can be mutually compensated. As a result, the upper base part 12 is relieved.

[0042] As in Figure 6 As shown in FIG. 1 , a bearing sleeve 26 is provided at the holding section 21 of the bearing bolt 16, at which the cutting tool 14 is held. As a result, the cutting tool 14 can swing around the bearing axis 32 of the bearing bolt 16. The bearing axis 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 floatingly 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 sintered metal, thereby reducing the friction between the cutting tool 14 and the bearing bolt 16. The heat generated during the swing between the bearing sleeve 26 and the cutting tool 14 is transferred to the upper base part 12 via the support plate 24.

[0043] The cutting tool 14 is held pivotably at one end in the pivot gap 28 of the cutting head 10 at the bearing sleeve 26 and projects with the other end out of the pivot gap 28. The pivot gap 28 is bounded by the underside 31 of the upper base part 12 and by the upper side 43 of the lower base part 13 facing the underside 31. When the cutting head 10 is mounted, the bearing bolt 16 extends over the entire height of the pivot gap 28 extending in the direction of the axis of rotation 17 and projects into the bolt opening 27 of the lower base part 13 provided for the bearing bolt 16. The bearing bolt 16 is also supported by the lower base part 13 when it is sunk into the bolt opening 27.

[0044] As in Figure 6As shown in the figure, the upper base part 12 has a through hole 46 extending coaxially to the rotation axis 17 for inserting a plug through the drive shaft 18. In the embodiment of the cutting head 10, no form fit is provided between the drive shaft 18 and the upper base part 12. In an alternative embodiment, a form fit can also be provided between the drive shaft 18 and the upper base part 12. In such an embodiment, the snap-on connection 1 is however designed to be rotatable at the retaining contour 4 so that the lower base part 13 can be rotated onto the drive shaft 18. If only the screw element 19 is designed to be rotatable relative to the lower base part 13, a rotatable snap-on connection 1 can be omitted.

[0045] The lower base part 13 is divided into an inner region 33 and an outer region 34 in the radial direction toward the axis of rotation 17. The inner region 33 of the lower base part 13 is designed as a dome 35, which extends into the central opening 36 of the upper base part 12. The central opening 36 is in particular pot-shaped and extends around the through hole 46. In the assembled state of the cutting head 10, the dome 35 contacts the upper base part 12 at the end side 50 of the central opening 36 with its end side 47 facing the lower side 31 of the upper base part 12. The end side 47 is part of the upper side 43 of the lower base part 13. The outer region 34 of the lower base part 13 is essentially used for fixing the cutting tool 14 in the receptacle 15 and forming the swing gap 28 between the upper base part 12 and the lower base part 13. In a preferred embodiment, the dome 35 of the lower base part 13 has a diameter e measured radially relative to the rotation axis 17, which corresponds in particular to at most 50% of the diameter d of the cutting head 10 measured radially relative to the rotation axis 17. In alternative embodiments of the cutting head 10, a dome with a larger diameter e may also be suitable. The screw element 19 is held in the dome 35 of the lower base part 13, in particular in a rotationally fixed manner.

[0046] As in Figure 7 , 8 , 13, 16, the cutting head 10 comprises a releasable snap-on connection 1. The snap-on connection 1 comprises at least one catch hook 2 and at least one retaining contour 4. The catch hook 2 is preferably designed to be bendable in a radial direction away from the axis of rotation 17. The at least one catch hook 2 is formed on the upper base part 12 and extends into the central opening 36 of the upper base part 12. A hook head 3 is formed at the end of the catch hook 2 facing the lower base part 13. The retaining contour 4 is formed on the lower base part 13, in particular on the dome 35 of the lower base part 13. The snap-on connection 1 is formed between the end sides 47, 50 of the base parts 12, 13 facing each other, namely the lower side 31 of the upper base part 12 and the upper side 43 of the lower base part 13. The catch hook 2 is arranged in a protective manner in the pot-shaped central opening 36 of the upper base part 12.

[0047] When the cutting head 10 is assembled, the upper base part 12 and the lower base part 13 are pushed together in such a way that the catch hook 2 penetrates into the holding opening 8 at the dome 35 and the catch hook 2 and the holding contour 4 are in operative connection. In this process, the catch hook 2 latches into the holding contour 4. The catch hook 2 grips the holding contour 4 from the rear with its hook head 3, whereby the snap-on connection 1 latches. The upper base part 12 and the lower base part 13 are connected by means of the snap-on connection 1. In the latched position, the snap-on connection 1 generates a holding force between the upper base part 12 and the lower base part 13, which acts essentially in the direction of the axis of rotation 17.

[0048] In order to release the hook-and-loop connection 1 again, the upper base part 12 and the lower base part 13 are pulled away from each other in the direction of the rotation axis 17. In this case, only the holding force of the hook-and-loop connection 1 has to be overcome. The holding head 3 has a contact surface 9, which produces an effective connection with the holding contour 4. The contact surface 9 is oriented obliquely to the rotation axis 17, i.e., with respect to the pulling direction of the upper base part 12 and the lower base part 13. If the operator pulls the base parts 12, 13 away from each other with sufficient pulling force, the hook head 3 slides off via its oblique contact surface 9 on the holding contour 4, whereby the catch hook 2 is pressed inwards towards the rotation axis 17. In this case, the hook-and-loop connection 1 is released and the base parts 12, 13 are separated from each other.

[0049] As in Figure 7 and Figure 8 As shown in the preferred embodiment, the snap-on connection 1 comprises two catch hooks 2 with corresponding retaining contours 4. In alternative embodiments, it may be expedient to also provide a plurality of catch hooks 2 with a plurality of retaining contours 4. If the snap-on connection 1 comprises a plurality of catch hooks 2, the catch hooks are preferably distributed at uniform angular spacings in the circumferential direction of the axis of rotation 17. The retaining force of the snap-on connection 1 can be increased by using a plurality of catch hooks 2. Alternatively, the contact surface 9 of the hook head 3 and the retaining contour 4 in active connection therewith can also be matched in order to set the retaining force to be achieved.

[0050] The cutting head 10 is fixed to the work tool in the following steps:

[0051] The operator turns the work tool 100 in such a way that the end of the drive shaft 18 is oriented relative to gravity. The upper base part 12 is then put on the drive shaft 18. The operator then puts the cutting tool 14 on the bearing screw 16, which is tightened on the upper base part 12. The operator pushes the lower base part 13 onto the upper base part 12 until the snap connection 1 is locked. The entire cutting head 10 is then screwed onto the drive shaft 18 via the screw element 19 on the lower base part 13. Alternatively, the base parts 12, 13 can be preassembled with the cutting tool 14 and then screwed onto the drive shaft 18.

[0052] The snap-on connection 1 enables the operator to pre-assemble the base parts 12, 13 with the cutting tool 14 and to screw the assembly consisting of the cutting head 10 and the cutting tool 14 together on the drive shaft 18 of the work device 100. This prevents the operator from losing individual parts when fastening the cutting head 10. This simplifies the assembly of the cutting head 10.

[0053] As in Figure 8 and Fig. 9 As shown in FIG. 1 , the cutting head 10 comprises an interference contour 40 and a guide groove 41. In the exemplary embodiment, the interference contour 40 is formed on the upper base part 12. The guide groove 41 is formed on the lower base part 13. In an alternative embodiment of the cutting head 10, it is obvious that the interference contour 40 can also be formed on the lower base part 13 and the guide groove 41 can be formed on the upper base part 12. As in particular in Fig.11 and Fig.12 As shown in the figure, the interference contour 40 is formed on the inner wall 37 of the upper base part 12. The interference contour 40 is designed as a rib 42 extending in the axial direction, that is, in the direction of the rotation axis 17. In order to avoid material accumulation due to production technology reasons, a recess is provided in the middle of the rib 42. The rib 42 protrudes from the inner wall 37 of the upper base part 12 into the central opening 36. In the exemplary embodiment, two interference contours 40 are provided, which have the same angular spacing from each other in the circumferential direction relative to the rotation axis 17.

[0054] exist Fig.14 and Fig.15 , a guide groove 41 is shown, which is formed on the dome 35 of the lower base part 13. The guide groove 41 extends from the end side of the dome 35 in the direction of the axis of rotation 17 away from the end side of the dome 35. In the present exemplary embodiment, two guide grooves 41 are provided, which are arranged at equal angular distances in the circumferential direction relative to the axis of rotation 17 similar to the interference contour 40. The number of guide grooves 41 on the dome 35 corresponds to the number of interference contours 40 on the inner wall 37 of the upper base part 12 in the exemplary embodiment. It can also be provided that there are fewer interference contours 40 than guide grooves 41.

[0055] During the assembly of the cutting head 10, the interaction of the interference contour 40 and the guide groove 41 ensures that the upper base part 12 and the lower base part 13 can only be assembled to each other in a predetermined position. For assembly, the base parts 12, 13 must therefore be aligned to each other in the circumferential direction. In this case, the upper base part 12 slides along the end face 47 of the dome 35 with its interference contour 40 until the operator aligns the base parts 12, 13 with each other by rotation in such a way that the interference contour 40 and the guide groove 41 are opposite each other in the direction of the rotation axis 17. The upper base part 12 has a flange 48 with a flange end side 49 that protrudes in the axial direction via the interference element 40, which reduces the radial alignment of the two base parts 12, 13 with each other during rotation by the operator. The interference contour 40 is designed here in such a way that it can slide into the guide groove 41 and the base parts 12, 13 can be pushed together.

[0056] The snap-on connection 1 and the interference contour 40 or the guide groove 41 are coordinated with each other in such a way that when the base part 12 is pushed together, the interference contour 40 must first slide into the guide groove 41 before the catch hook 2 can be inserted into the holding opening 8. Due to the contact between the interference contour 40 and the guide groove 41, a torque between the base parts 12, 13 can be transmitted in the circumferential direction relative to the rotation axis 17. This has the effect that the base parts 12, 13 can no longer rotate relative to each other when the catch hook 2 is inserted into the holding opening 3 at the dome 35. The base parts 12, 13 are connected to each other 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 positive connection in the circumferential direction relative to the rotation axis 17. In this way, an unintentional rotation of the base parts 12, 13 by the operator is avoided. Thus, a breakage of the catch hook 2 during the assembly process of the cutting head 10 can be prevented. The catch hook 2 of the snap-on connection 1 is protected by the interference contour 40 and the guide groove 41 during assembly.

[0057] As in Fig. 9, the thread of the screw element 19 has a thread length g measured in the direction of the rotation axis 17. The upper base part 12 has an axially measured total immersion depth h, 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 contour 40 has an axially measured length i from the end side 50 of the central opening 36 to the end side of the interference contour 40. The catch hook 2 also has an immersion depth j, which extends axially from the end side 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 when the base parts 12, 13 are assembled, they are first guided radially through the flange 48. The length i of the interference contour 40 is greater than the immersion depth j of the catch hook 2, so that first the interference contour 40 engages with the guide groove 41 and only then the catch hook 2 engages in the retaining contour 4. The length i of the interference contour 40 is at least 120%, in particular 150%, preferably approximately 200% of the immersion depth j of the catch hook 2. In this case, the interference contour j preferably corresponds approximately to the thread length g of the screw element 19 .

[0058] As in Fig.12 As shown in the figure, 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 cutting wire receptacle. The catch hook 2 is preferably arranged centrally between mutually adjacent bearing bolts 16 and the interference contour 40. Depending on the design of the base parts 12, 13 and the corresponding reinforcement ribs, the catch hook 2 can also be arranged eccentrically between the bearing bolt 16 and the interference contour 40.

[0059] exist Fig.10 , a cross-sectional view of a cutting head 10 is shown, in which the cutting tool 14 is swiveled out to its maximum extent. The swivel angle α is produced by two opposite swivel stops of the base body 11 for the respective cutting tool 14. Fig.10 The maximum swivel angle α of the cutting tool 14 is shown in FIG. 1 , which is measured from the major axis 29 of the cutting tool 14 in the circumferential direction relative to the bearing bolt 16. The swivel angle α is preferably at least 60°, preferably at least 120°, in particular approximately 200°. The swivel plane of the cutting tool 14 is arranged perpendicular to the axis of rotation 17. As shown in FIG. Figure 7 As shown in FIG. 1 , the snap-on connection 1 has a distance a measured in the radial direction relative to the rotation axis 17, which is at most 40%, preferably at most 30%, in particular 25% of the diameter d of the cutting head 10. The bearing axis 32 has a distance f relative to the rotation axis 17. The distance f between the bearing axis 32 and the rotation axis 17 is greater than the distance a between the snap-on connection 1 and the rotation axis 17 (see FIG. Fig.12). The snap-on connection 1 is therefore located in the radial direction relative to the axis of rotation 17 within the bearing shaft 32 of the bearing bolt 16. By configuring the snap-on connection 1 near the axis of rotation 17, the structural element is displaced into the inner region of the cutting head 10. As a result, the swing play 28 can be kept free accordingly and a larger swing angle ß can be achieved. In addition, 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.

Claims

1. Cutting head for motorized sickle, It comprises a divided base body (11) with an upper base body part (12) and a lower base body part (13), A screw element (19) is arranged on the lower base part (13), wherein the screw element (19) is used for fixing on a drive shaft (18) of a motorized sickle. in, At least one receiving portion (15) is provided between the upper base member (12) and the lower base member (13) for fixing a cutting tool (14). The base body (11) can be driven to rotate around its rotation axis (17) during the operation of the motorized sickle. The upper base part (12) and the lower base part (13) are held together by means of a releasable snap connection (1), characterized in that the snap connection (1) has a distance a measured in the radial direction relative to the rotation axis (17), which is at most 40% of the diameter d of the cutting head (10), and the snap connection is arranged in an inner area of ​​the cutting head and is thus protected.

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

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

4. The cutting head according to claim 1, characterized in that: The hook-and-loop connection (1) comprises at least one catch hook (2) and at least one retaining contour (4) which is in operative connection with the catch hook (2).

5. The cutting head according to claim 4, characterized in that: The catch hook (2) is arranged on the upper base part (12) and the at least one retaining contour (4) is arranged on the lower base part (13).

6. The cutting head according to claim 4, characterized in that: The at least one catch hook (2) has a hook head (3) which is designed to grip the at least one retaining contour (4) from behind.

7. The cutting head according to claim 6, characterized in that: The hook (3) is designed in such a way that the hook-and-loop connection (1) locks when the base parts (12, 13) are pressed together and unlocks when the base parts (12, 13) are pulled away from each other.

8. The cutting head according to claim 1, characterized in that: An interference contour (40) is provided on one of the two base parts (12, 13), and a guide groove (41) extending in the direction of the rotation axis (17) and cooperating with the interference contour (40) is provided on the other base part (12, 13), so that the upper base part (12) and the lower base part (13) are aligned with each other in the circumferential direction of the rotation axis (17) by means of the interference contour (40) and the guide groove (41).

9. The cutting head according to claim 8, characterized in that: The snap-on connection (1) is designed in such a way that it can only be locked when the upper base part (12) and the lower base part (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 A torque can be transmitted in the circumferential direction between the upper base part (12) and the lower base part (13) via the interference contour (40) and the guide groove (41).

11. The cutting head according to claim 1, characterized in that: The receptacle (15) is designed as a bearing screw (16) and the cutting tool (14) can be arranged on the base body (11) via the bearing screw (16).

12. The cutting head according to claim 11, characterized in that The bearing pin (16) is fixed on one side to the upper base part (12) or the lower base part (13).

13. The cutting head according to claim 11, characterized in that The bearing bolt (16) is fixed to the upper base member (12).

14. The cutting head according to claim 1, characterized in that The screw element (19) is arranged on the lower base part (13) in a rotationally fixed manner.

15. The cutting head according to claim 1, characterized in that The cutting tool (14) is arranged pivotably on the at least one receptacle (15).

Images