Abstract:
The invention relates to a guide element for an agricultural soil-cultivation machine comprising a connection region for arranging the guide element on a share tip, and comprising a first screw connection for attaching the guide element on a holder, in particular on a tine of the soil-cultivation machine. The guide element has varying thickness, at least in regions along the longitudinal extension thereof running from the connection region to a turned-away end region. The invention further relates to a corresponding tool combination comprising capacity of the guide element to be conformed to the loads in the tool insert, and thus conforming of the maintenance interval to that of the share tip.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a continuation of International Application No. PCT/EP2015/076488 filed Nov. 12, 2015, which designated the United States, and claims the benefit under 35 USC §119(a)-(d) of German Application No. 10 2014 116 619.1 filed Nov. 13, 2014, the entireties of which are incorporated herein by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to a guide element for an agricultural soil-cultivation machine comprising a connection region for arranging the guide element on a share tip, and comprising a first screw connection for attaching the guide element on a holder, in particular, on a tine of the soil-cultivation machine. 
         [0003]    The present invention further relates to a tool combination with a guide element and a share tip for an agricultural soil-cultivation machine, having a connection region of the guide element for arranging the guide element on a share tip, and having a first screw connection for attaching the guide element on a holder, in particular, on a tine of the soil-cultivation machine, wherein a thickness of the guide element in the connection region corresponds to a thickness of the share tip at its end, facing the guide element, within predefined tolerances. 
       BACKGROUND OF THE INVENTION 
       [0004]    DE 3628910 A1 discloses a tool combination, having a blade tip and a guide plate, which can be mounted together on a blade of a tine of a soil-cultivation machine. The share tip and the guide plate are connected together by a form-fitting connection, so that only one fastening screw is required for attaching the guide plate and the share tip to the blade. The form-fitting connection is formed by a tappet on the share tip, which engages with a corresponding recess in the guide plate. At its free end, the guide plate is bent around the blade to safely deflect the flow of soil from the blade at the upper free end of the guide plate and push it away in the intended direction. The bending achieves a form-fitting connection between the guide plate and the blade so that the guide plate can be attached to the blade with only one fastening screw. 
         [0005]    A disadvantage of the disclosed tool combination is that the share tip, which is exposed to much heavier load than the guide plate during use, wears faster than the guide plate and, accordingly, must be replaced sooner. Due to the exposed form-fitting connection, deformations can be introduced in the area between the guide plate and the share tip during operation, preventing, or at least impeding, removal of the share tip from the guide element. This results in increased maintenance effort, during which a guide element that is not worn may have to be replaced. A further disadvantage arises from the fact that the guide element is more heavily stressed in its connection region to the share tip than at its free end. Replacement of the guide element is thus determined by its wear in the connection region, while the free end is still intact. The same applies to the share tip, which wears significantly faster at its front cutting edge than at its end facing the guide element. The tool combination shown, therefore, results in uneven wear behaviour of the components used with respect to each other and within the components. As a result, the most heavily stressed components or component portions determine the service life of the tool combination, and, thus, the maintenance intervals. During the required replacement, generally intact components or component portions must be replaced as well. 
         [0006]    DE 10 2011 102 053 A1 discloses a tool combination having a share tip, which can be mounted on a tine of a soil-cultivation machine. The share tip is formed from a carrier part, the cutting end of which is equipped with a cutting element made of hard metal. On the side of the cutting element, secondary cutters are soldered to the carrier part at an angle. Adjacent to the carrier part, a guide plate is provided, which encloses the tine partially at its free end. A guide part is provided, which covers the carrier part with the exception of the cutting elements and secondary cutters. The guide part is connected to the guide plate in a form-fitting manner and is detachably connected to the carrier part. The multi-part construction makes it possible to replace only the functional components that are worn. The present document assumes that it is extremely unlikely that all functional components will become worn at the same time and, therefore, they must be replaced separately. This also applies to an embodiment of the present invention in which the guide plate and the guide part are designed as a single component. Here, the document provides a symmetrically constructed, and thus rotatable, guide plate so that the end facing the carrier part can be rotated when worn and continued to be used. 
         [0007]    Here, too, there is the disadvantage that, due to the exposed form-fitting connection, deformations may be introduced in the region between the guide plate and the carrier part or the guide part, preventing, or at least impeding, separation of the components. This results in increased maintenance effort, during which components that are not worn may have to be replaced. Due to the different service life of the various functional components, frequent maintenance with associated downtimes of the soil-cultivation machine are required. 
       SUMMARY OF THE INVENTION 
       [0008]    It is an object of the present invention to provide a guide element of the aforementioned kind and a tool combination having such a guide element, resulting in reduced maintenance effort. 
         [0009]    The object of the present invention with regard to the share tip is solved by the fact that the guide element has varying thickness, at least in regions along the longitudinal extension thereof running from the connection region to a turned-away end region. The thickness of the guide element in the various regions of the guide element can thus be adapted to the stress occurring there, and hence to the wear occurring there. Areas that are exposed to high stress are formed thicker than regions with lower stress. This ensures that the guide element has a comparable service life in all regions. With these measures, maintenance intervals can be extended, when compared to guide elements with consistent thickness, and comparable maintenance intervals can be achieved with reduced use of material. Furthermore, the change intervals of the guide element can be adapted to the change intervals of a connected share tip, significantly reducing the total required maintenance effort. A reduced use of materials advantageously results in reduced manufacturing costs and a reduction in weight of the guide element. In particular, if a plurality of guide elements is attached to the soil-cultivation machine, the weight reduction results in a reduction of the total stress on the soil-cultivation machine as well as of the fuel consumption of a drive unit of the soil-cultivation machine. The guide element may be manufactured, for example, as a forged part and thus be designed to be very strong and resistant to abrasion. 
         [0010]    The mechanical stress of the guide element is greatest adjacent to the share tip. Therefore, it can be provided that the guide element has its greatest thickness in the connection region facing the share tip. 
         [0011]    The mechanical stress, and thus the abrasion, of the guide element are lowest in its end region facing away from the share tip. In order to achieve a comparable service life between the connection region and the end region of the guide element, it can therefore be provided that the thickness of the guide element is smallest in its end region facing away from the share tip. 
         [0012]    A comparable service life over the entire length of the guide element can be achieved by the thickness of the guide element decreasing continuously from the connection region to the end region. 
         [0013]    According to a particularly preferred embodiment of the present invention, it can be provided that the thickness of the guide element in its connection region corresponds to the thickness of the share tip associated with the guide element at its end facing the guide element within predetermined tolerances. For the passing soil, this results in a continuous transition without pronounced steps where increased wear occurs. Furthermore, the same thickness of the guide element and of the share tip in their adjoining regions results in comparable service lives of the two components in these regions. If the remaining regions of the share tip and the guide element are adapted by means of corresponding thickness variations or, for example, by local coating with hard material elements, so that they have a service life comparable to the adjacent regions, the share tip and the guide element, as well as the components within themselves in the various regions, will have a comparable service life, and thus comparable maintenance intervals. The components can thus be replaced as the same time, resulting in reduced maintenance effort and reduced downtime of the soil-cultivation machine. 
         [0014]    The guide element is mounted to the carrier with a first screw connection. A secure and wear-resistant first screw connection can be achieved by the first screw connection being arranged in the connection region of the guide element and/or by a first screw head of a first fastening screw of the first screw connection being arranged in a countersunk position relative to a deflecting surface of the guide element. Fastening of the guide element is thus done in the area of its greatest material thickness, resulting in a resilient connection between the guide element and the carrier. Due to the recessed screw head, it is protected from passing soil and thus from abrasive wear. The wear protection is further improved by the fact that soil sticks above the screw head in the screw receptacle and thus shields the screw head from the passing soil. Due to the present high material strength, the screw receptacle can be designed correspondingly deep. The screw head is therefore countersunk with respect to the deflection surface of the guide element, and thus protected against wear, even after severe abrasion of the guide element has taken place. The guide element is thus securely held on the carrier until replacement is required. 
         [0015]    According to the present invention, it can be provided that the guide element can be constructed for its back side to be in contact with the carrier and/or that the guide element has protruding bridges on its back side, arranged spaced from each other, and/or that a guide receptacle for the carrier is formed between the bridges. By a rear contact of the guide element with the carrier, high resilience against deformation is achieved even in areas of reduced thickness of the guide element since forces applied to the guide element against a tool feed direction are transferred to the carrier. The lateral bridges allow for simple mounting of the guide element, since the guide element can be easily aligned with respect to the carrier due to the bridges and the guide receptacle. A further advantage of the bridges results from the fact that they absorb lateral loads on the guide plate during operation. The guide element is thus affixed on the carrier in a form-fitting manner, transversely to the tool feed direction. 
         [0016]    The bridges can be advantageously arranged in the connection region and/or in the end region of the guide element. In these regions, the bridges accomplish the best possible lateral guiding of the guide element. Compared to longer bridges, for example, ones that are continuous from the connection region to the end region, there is an advantage in material optimization and, as a result, a correspondingly lower weight of the guide element with the same attainable level of lateral guiding. 
         [0017]    Transverse forces acting on the guide element can be especially well absorbed due to the two bridges being arranged opposite of one another on both sides of the carrier and/or the bridges having drafts on their sides facing the carrier, such that their mutual distance increases with increasing distance from the back side of the guide element. The drafts facilitate mounting of the guide element to the carrier since the guide element aligns itself to the carrier. Due to the drafts, a guide receptacle is achieved that is widening outwards and into which the carrier can be easily inserted. The widening guide receptacle allows manufacturing the guide element by forging. 
         [0018]    A rear support of the guide element in the region of the bridges may be achieved by the fact that a contact surface for contact of the guide element with the carrier is formed between the bridges and/or that clearances in the form of grooves are provided in the transition from the drafts to the contact surface. The clearances accommodate the edges of the carrier. This achieves a large area of contact of the contact surface of the guide element on the carrier even if the same has a manufacturing-related burr, for example, at the edges. 
         [0019]    According to one embodiment of the present invention, it can be provided that the bridges have outer bridge surfaces on their side facing away from the guide element and that the transitions from the drafts to the outer bridge surfaces are rounded. The rounded transitions from the drafts to the outer bridge surfaces prevent tilting of the guide element with respect to the carrier during assembly. Due to the rounded transitions and the adjacent drafts, the guide element can be aligned simply on the carrier and can self-align. In addition, the rounded transitions result in a stress-optimized construction in which stress spikes, as occur in the area of sharp edges under mechanical load, can be avoided. 
         [0020]    The guide element and an associated share tip can be aligned with each other, by the guide element having an attachment, in particular, a plug attachment, in the connection region for affixing it in a receptacle of the share tip. 
         [0021]    According to a particularly preferred embodiment of the present invention, it may be provided in this case that the shape of the attachment of the guide element is designed such that it can be connected only with a share tip that is uniquely associated to it by a receptacle that is adapted to it in its shape. This achieves an encoding in the assignment of a guide element to a share tip, resulting in only an associated type of guide element being connectable to a certain design of a share tip. As a result of this measure, only those share tips and guide elements can be connected together that are matched to one another, for example, in their wear behaviour. For example, share tip types with different thickness may be provided where a type of guide element with matched thickness in the connection region is uniquely associated. 
         [0022]    Such an encoding between the guide element and the share tip can be effected by the attachment of the leading element being equipped with at least one projection and/or at least one recess for cooperating with a receptacle and/or an attachment molded on the share tip. 
         [0023]    In addition to the first screw connection, effective affixing on the guide element can be achieved by the attachment and the receptacle forming a form-fitting connection. The guide element with its attachment is thus held in the receptacle of the share tip in a form-fitting manner. 
         [0024]    A possible embodiment of the present invention is characterized in that the guide element  30  is integrally formed on the share tip  40 . This reduces the cost for parts and assembly. In addition, a homogenized flow of the crop material on the surface can be achieved. 
         [0025]    One conceivable embodiment of the present invention can be designed such that the front side  32 . 1  of the guide element  30  forming the guide surface coils in the region between the end facing the share tip  40  and the end facing away from the share tip  40 . This allows the crop flow to be directed to the side of the cultivator. In particular, this continuously targeted deflection may reduce the tractive force requirements. Here, not only the front, but, in particular, the entire guide element may be twisted or coiled. This reduces the parts cost. Preferably the guide element should be coiled in the range between 50° and 80°. Optimum deflection is achieved in the range between 15° and 70°. 
         [0026]    The object of the present invention with regard to the tool combination is solved by the fact that the guide element has varying thickness, at least in regions along the longitudinal extension thereof running from the connection region to a turned-away end region. Due to the varying thickness, the resilience of the different regions of the guide element can be adapted to the respective loads present during use of the tool so that at least approximately equal service life is achieved over the entire longitudinal extension of the guide element. The guide element does therefore not have to be replaced prematurely because a particularly heavily stressed region is worn out prematurely. Due to the thickness of the guide element being locally adapted to its load, its service life can be adapted to the connected share tip so that the same replacement intervals are advantageously achieved for the guide element and the share tip. 
         [0027]    An adjustment of the thickness of the guide element to the stress actually present during use of the tool can be achieved by the thickness of the guide element decreasing from the connection region toward an end region of the guide element, opposite the connection region. 
         [0028]    According to a preferred embodiment of the present invention, it can be provided that the share tip has a receptacle, which is covered by a covering portion in the tool feed direction (V), that the guide element has an attachment, in particular a plug attachment, and that a connection, in particular a form-fitting connection, formed by a receptacle and an attachment engaging therewith, is effective in the region of the receptacle between the share tip and the guide element. Due to the form-fitting connection, the guide element is securely attached to the share tip and aligned with respect to the same. The covering portion prevents the region of the form-fitting connection from being directly exposed to the passing soil. The form-fitting connection is thus protected against abrasive wear. Furthermore, the attachment is held by the covering portion, so that it will not buckle under load. This achieves a much longer service life of the form-fitting connection compared to a form-fitting connection that is open in the tool feed direction. Due to the reduced wear of the attachment and the receptacle, the share tip and the guide element can be easily and reliably separated from each other even after high mechanical stress, keeping the maintenance effort when changing the guide element and/or the share tip low. 
         [0029]    Unique assignment of a share tip to a guide element matched to it in terms of its wear can be achieved by selecting the shape of the attachment, in particular the plug attachment, depending on the thickness of the guide element in its end region, and the shape of the receptacle of the share tip depending on the thickness of the share tip at its end facing the guide element end, such that the attachment, in particular the plug attachment, and the receptacle are connectable only with identical thickness of the guide element in its connection region and of the share tip at its end facing the guide element. Due to the design of the receptacle and the attachment, only guide elements and share tips with identical thickness in their transition region will match each other. Due to this encoding, it can be ensured that only those guide elements can be assigned to the respective share tips for which the service life is accordingly matched to the service life of the share tips. 
         [0030]    Preferably, it can be provided that the guide element along its longitudinal extension, preferably in its end region, or otherwise at any point on the front side  32 . 1 . is concavely shaped in a tool feed direction (V) so that the share tip, along its longitudinal extension at least in a portion facing the guide element, is concavely shaped in the tool feed direction (V) and that the radii of the concavely shaped portions, at least in the connection region of the guide element and the portion of the share tip facing the guide element, are identical within manufacturing-related tolerances and/or that the concave portions transition into one another. A uniform passage of the soil from the share tip to the guide element is achieved without creating any areas of increased resistance, and thus abrasion. 
         [0031]    The front side  32 . 1  of the guide element can have different designs within the scope of the present invention. Thus, it is possible that the front side  32 . 1  may be designed at least partially concave, convex, or corrugated. A concave geometry forms a channel in the longitudinal direction of the guide element for directional guiding of the material. With a convex design, the material is deflected to either side of the cultivator. This creates compression and expansion zones in the longitudinal direction of the guide element in favor of an improved wear behaviour. Here, corrugation can already offer a significant advantage. Instead of a concave or convex contour, attached surface geometries may be provided as well. A varying width of the guide element may be provided in the width direction as well in order to influence the conveying effect in a targeted manner. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0032]    The present invention is explained in further detail below on the basis of an embodiment shown in the figures. 
           [0033]      FIG. 1  shows a front view of a cultivator share, having a blade tip and a guiding element; 
           [0034]      FIG. 2  shows a detail of the cultivator share, shown in  FIG. 1 , in the region of the share tip and the guide element, in a lateral sectional view; 
           [0035]      FIG. 3  shows the guide element with a tine in an end region of the guide element in a first embodiment in a sectional view extending in a direction transverse to the longitudinal extension of the guide element; 
           [0036]      FIG. 4  shows the guide element and the tine in an end region of the guide element in a second embodiment in a sectional view extending in a direction transverse to the longitudinal extension of the guide element; 
           [0037]      FIG. 5  shows the guide element and the tine in a connection region of the guide element in a first embodiment in a sectional view extending in a direction transverse to the longitudinal extension of the guide element; 
           [0038]      FIG. 6  shows the guide element and the tine in a connection region of the guide element in a second embodiment in a sectional view extending in a direction transverse to the longitudinal extension of the guide element; 
           [0039]      FIG. 7  shows a detail of the lateral sectional view, shown in  FIG. 2 , in the region of a form-fitting connection; 
           [0040]      FIG. 8  shows the section of the form-fitting connection, shown in  FIG. 7 , in a partially sectioned rear view; 
           [0041]      FIG. 9  shows the detail, shown in  FIG. 7 , in a second embodiment of the form-fitting connection; 
           [0042]      FIG. 10  shows the section, shown in  FIG. 9 , in a partially sectioned rear view; and 
           [0043]      FIG. 11  shows the detail, shown in  FIGS. 8 and 10 , in a third embodiment of the form-fitting connection. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0044]      FIG. 1  shows a front view of a cultivator share  10 , having a blade tip  40  and a guide element  30 . The cultivator share  10  can be attached to a tool carrier, in particular, a tine  20  or tine carrier or plow beam or the like of an agricultural soil-working machine. For this purpose, the guide element  30  has a first screw receptacle  31  and the share tip  40  has a second screw receptacle  42  and a third screw receptacle  43 . The tine  20  has a fastening part  21 , not shown, which is pierced by fastening bores. By means of these fastening bores, the tine  20  can be mounted on a device carrier. On the side facing the soil  60  to be cultivated, the share tip  30  ends in two front cutting elements  50 , with which two hard material elements  51  are associated on the side. 
         [0045]      FIG. 2  shows a detail of the cultivator share  10 , shown in  FIG. 1 , in the region of the share tip  40  and the guide element  30 , in a lateral sectional view. The section in this case runs along the cutting line indicated by II in  FIG. 1 . 
         [0046]    The tine  20  has a carrier part  21 , shown in  FIG. 1 , in a region facing away from the carrier part  22 . The share tip  40  and the guide element  30  are mounted on this carrier part  22 . 
         [0047]    The guide element  30  is aligned with a deflecting surface  32 . 1  toward the tool feed direction V. The guide element  30  abuts against the carrier part  22  of the tine  20  with a back side  32 . 2 . The guide element  30  is concavely curved in the tool feed direction V, starting from a connection region  30 . 3  facing the share tip  40 , via a central region  30 . 2 , to an end region  30 . 1  facing away from the share tip  40 . In this case, the thickness  38 . 1 ,  38 . 2 , of the guide element  30 , indicated by double arrows in  FIGS. 3 to 6 , continuously decreases from the connection region  30 . 3  to the end region  30 . 1 . 
         [0048]    The carrier part  22  of the tine  20  has a first bore  23 . 1 , a second bore  23 . 2 , and a third bore  23 . 3  for fastening the guide element  30  and the blade tip  40 . The first bore  23 . 1  is arranged flush with the first screw receptacle  31  mounted in the guide element  30 . The guide element  30  is mounted to the carrier part  22  above the share tip  40  with a first fastening screw  12 , which is inserted through the first screw receptacle  31  of the guide element  30  and the first bore  23 . 1  in the tine  20 , as well as with an associated upper screw nut  12 . 3 . A first screw head  12 . 1  of the upper fastening screw  12  is designed as a countersunk head and fits into the first screw receptacle  31 , designed as a countersunk bore, such that the surface of the upper screw head  12 . 1  is arranged set back from the deflecting surface  32 . 1  of the guide element  30 . The upper screw head  12 . 1  is thus protected against abrasive wear caused by the passing soil. 
         [0049]    The share tip  40  is arranged adjacent to the connection region  30 . 3  of the guide element  30  and connected thereto by a form-fitting connection, more clearly shown in  FIGS. 7 and 8 . 
         [0050]    The share tip  40  has a base part  41  which is penetrated by the second and third screw receptacle  42 ,  43 . A deflector  44 . 1  is provided in the form of a projection below the third screw receptacle  43 , protruding in the form of a deflector over a front-side deflecting surface  44  of the base part  41 . In this manner, the deflector  44 . 1  forms a skirt that protects a third screw head  14 . 1  arranged in the third screw receptacle  33  of a third fastening screw  14  against the abrasive attack by the passing soil. In front of the deflector  44 . 1  in the tool feed direction V, the base part  41  has steps  45  which protrude over the deflecting surface  44 . In the present exemplary embodiment, the attachments  35  are rib-shaped and oriented transversely with respect to the tool feed direction V. Depressions  46  are formed between the individual steps  45 . During use of the tool, the soil may compress and settle into the region of the depressions  46 . This forms a kind of natural wear protection on the front-side deflecting surface  44 . 
         [0051]    In front of the steps  45  in the tool feed direction V, the front cutting elements  47  are attached to a cutting element  50  in the form of hard metal elements, which form a cutter  50 . 3  as the front edge of the share tip  40 . The cutting elements  50  have a flat-shaped mounting portion  50 . 1  and an attachment piece  50 . 2 , integrally molded thereon and projecting against the tool feed direction V. The cutter  50 . 3  is formed in the region of the attachment piece  50 . 2 . The cutting elements  50  are attached to the cutter carrier  47  such that the free terminating edge of the cutter carrier  47  is at least partially surrounded by the attachment pieces  50 . 2  of the cutting elements  50 . In this manner, the free end of the cutter carrier  47  is protected against wear. 
         [0052]    Behind the cutting elements  50  in the tool feed direction V, the hard material elements  51 , shown in  FIG. 1 , are applied on the edge regions of the base part  41 , which are subjected to particularly high wear. In the present case, hard metal plates are soldered to the base part  41  as the hard material elements  51 . However, it is also conceivable to use an armor welding or the like. Opposite the hard material elements  51 , the base part  41  is reinforced by projections  48  extending along its edges. 
         [0053]    The second screw receptacle  42  and the third screw receptacle  43  of the share tip  40  are aligned flush with the second bore  23 . 2  and aligned third bore  23 . 3 . Inserted through the second screw receptacle  42  and the second bore  23 . 2 , there is a second fastening screw  13 , held by a second screw nut  13 . 3 . A second screw head  13 . 1  is countersunk and thus held in the second screw receptacle  42 , protected against abrasive wear. The third fastening screw  14  is inserted through the third screw receptacle  43  and the third bore  23  and held by a third screw nut  14 . 3 . The guide element  30  is thus mounted to the carrier part  22  of the tine  20  by a first screw connection  11 . 1 , and the share tip  40  by a second and a third screw connection  11 . 2 ,  11 . 3 . 
         [0054]    The cultivator share  10  is pulled through the soil  60  to be cultivated by the agricultural soil cultivation machine along the illustrated tool feed direction V. Here, the soil is removed from the cutting elements  50  and deflected away over the front-side deflecting surface  44  of the share tip  40  and the adjacent deflecting surface  32 . 1  of the guide element  30 . In the embodiment shown, the guide element  30  is designed straight, transverse to the tool feed direction V. In some cases, helical deflecting surfaces are used as well. The share tip  40  and the guide element  30  are concave along their longitudinal extension in the tool feed direction V. The radius of the front-side deflecting surface  44  of the share tip  40  in the transition region to the guide element  30  corresponds to the radius of the deflecting surface  32 . 1  in the connection region  30 . 3  of the guide element  30 . Removed soil can thus be guided away from the share tip  40  via the guide element  30  in a flowing movement. 
         [0055]    According to the present invention, the thickness  38 . 1 ,  38 . 2 , of the guide element  30  varies over its longitudinal extension. It has the greatest thickness  38 . 2  in the connection region  30 . 3 , which is adapted to the thickness of the adjacent share tip  40  in its region facing the guide element  30 . Thus, there is a continuous transition from the front-side deflecting surface  44  of the share tip  40  to the deflecting surface  32 . 1  of the guide element  30 . The soil can thereby be guided uniformly from the share tip  40  to the guide element  30 . Open edges, on which the passing soil is caught, are avoided, resulting in a significant reduction of abrasion, and thus wear, in this region. 
         [0056]    The mechanical stress on the cultivator share  10  decreases, starting from the cutting elements  50  to the end region  30 . 1  of the guide element  30 . The most heavily stressed area of the cultivator share  10  is protected by the cutting elements  50 , formed of a hard material, and the adjacent hard material elements  51 . The adjoining region of the share tip  40  is designed particularly thick and is additionally protected against abrasion by the steps  45  and depressions  46 . The deflector  44 . 1  forms a protection of the adjacent attachment region of the share tip  40  by deflecting the passing soil. The share tip  40  is therefore designed in accordance with the different loads occurring along its longitudinal extension such that a similar service life during operation of the various regions of the share tip  40  is achieved. 
         [0057]    The guide element  30  is most highly stressed in the connection region  30 . 3  adjacent to the share tip  40 , whereas the load decreases from the central region  30 . 2  towards the end region  30 . 1 . Accordingly, the guide element  30  is designed such that it has its greatest thickness  38 . 2  in the connection region  30 . 3 . The thickness  38 . 1 ,  38 . 2 , of the guide element  30  decreases in accordance with the mechanical stress at the tool insert, over the central region  30 . 2 , to its smallest thickness  38 . 1  in the end region  30 . 1 . In operation of the cultivator share  10 , uniform service life of the various regions of the guide element  30  is thus achieved. Due to the identical thickness  38 . 1 ,  38 . 2  of the guide element  30  and the share tip  40  in their transition region, it is achieved that the service life of the guide element  30  and the share tip  40  are at least approximately equal as well. Thus, it follows that the guide element  30  and the share tip  40  can be replaced at the same time, resulting in a significant reduction in maintenance work, and consequently downtime of soil-cultivation machine. 
         [0058]    In known guide elements  30 , in which the local material thickness is not adapted to the respectively present load, the thickness of the material is chosen such that the service life in the most heavily stressed region corresponds to the expected values. There is thus an unnecessarily large material thickness in less heavily stressed regions. This can be avoided by the thickness that, according to the present invention, is adapted to the expected load. Compared to known guide elements  30 , the material used can be decreased with identical or even extended service life of the guide element  30 . Manufacturing costs can thus be reduced. Furthermore, the weight of the cultivator share  10  is reduced, resulting in a reduction in the load on the soil-cultivation machine as well as in fuel consumption, in particular, if a plurality of cultivator shares  10  are attached to the soil-cultivation machine. 
         [0059]    The guide element  30  is attached in the connection region  30 . 3 , and therefore in the region of the greatest thickness  38 . 2  of the guide element  30  by means of the first screw connection  11 . 1 . The great material thickness in this area allows for a particularly sturdy connection between the guide element  30  and the tine  20 . The first screw receptacle  31  may be designed accordingly deep so that the first screw head  12 . 1  of the first fixing screw  12  is positioned far below the deflecting surface  32 . 1  of the guide element  30 . In the cavity of the first screw receptacle  31  located above the first screw head  12 . 1 , soil may settle and thus further protect the screw head  12 . 1  from passing soil during operation. The first screw head  12 . 1  is thus optimally protected against wear. 
         [0060]      FIG. 3  shows the guide element  30  with a tine  20  in an end region  30 . 1  of the guide element  30  in a first embodiment in a sectional view extending in a direction transverse to the longitudinal extension of the guide element  30 . The section in this case runs along the cutting line indicated by III in  FIG. 2 . 
         [0061]    The guide element  30  abuts on a front side  24  of the carrier part  22  of the tine  20  with its back side  32 . 2 , designed as a flat surface. A surface normal of the deflecting surface  32 . 1  points approximately in the tool feed direction V of the cultivator share  10 . The removed soil pushes the guide element  30  against the front side  24  of the carrier part  22  so that the forces occurring are absorbed by the tine  20 . 
         [0062]    The guide element  30  has its smallest thickness  38 . 1  in the illustrated end region  30 . 1 , which is mechanical least stressed. 
         [0063]      FIG. 4  shows the guide element  30  and the tine  20  in an end region  30 . 1  of the guide element  30  in a second embodiment in a sectional view extending in a direction transverse to the longitudinal extension of the guide element. The section extends along the same section line as that in  FIG. 3 . 
         [0064]    Unlike in the embodiment shown in  FIG. 3 , a first crosspiece  33  and second crosspiece  34  are molded to the side of the carrier part  22  of the tine  20  on the back side  32 . 2  of the guide element  30 . As a result, a guide receptacle  32 . 4  for the carrier part  22  is formed between the crosspieces  33 ,  34 . The crosspieces  33 ,  34 , protrude over the back side  32 . 2  of the guide element  30  and each form an outer crosspiece surface  33 . 1 ,  34 . 1 . The outer crosspiece surfaces  33 . 1 ,  34 . 1  transition into the rounded drafts  33 . 3 ,  34 . 3  via radial transitions  33 . 2 ,  34 . 2 . The drafts  33 . 3 ,  34 . 3  are transitioned as clearances  35 . 1 ,  35 . 2 , designed as grooves, into a contact surface  32 . 3 , which is disposed in the same plane as the back side  32 . 2  of the guide element  30 . The guide element  30  abuts on a front side  24  of the carrier part  22  of the tine  20  with its contact surface  32 . 3 . The drafts  33 . 3 ,  34 . 3 , are oriented such that their distance increases outwardly, starting from their transition to the contact surface  32 . 3 . 
         [0065]    In the direction of the longitudinal extension of the guide element  30 , the crosspieces  33 ,  34 , are limited to the end region  30 . 1  of the guide element  30 . 
         [0066]    The guide element  30  is disposed laterally to the carrier part  22  of the tine  20  in the guide receptacle  32 . 4 . This allows for accurate and quick alignment of the guide element  30  with respect to the tine  20  during assembly. When tightening the first screw connection  11 . 1  during assembly, the guide element  30  is secured against rotation by the crosspieces. The same is true when releasing the guide element  30 , significantly facilitating the assembly and disassembly of the guide element  30 . During operation, transverse forces transferred to the guide element  30  are transferred to the carrier part  22  of the tine  20  by the crosspieces  33 ,  34 , and thus absorbed. Deformations of the guide part  30 , in particular in its end region  30 . 1  of reduced thickness  38 . 1 ,  38 . 2 , can thus be avoided. The attachment of the crosspieces  33 ,  34 , in the end region  30 . 1  of the guide element  30  results in a maximum Possible lever with respect to the first screw connection  11 . 1 . Thereby, torques transferred to the guide element  30  due to lateral forces can be absorbed with the least possible force, and hence least possible load on the crosspieces  33 ,  34 . 
         [0067]    By means of the drafts  33 . 3 ,  34 . 3 , of the crosspieces  33 ,  34 , it is achieved that the guide element  30  can be positioned easily on the carrier part  22  of the tine  20  and will self-align during assembly. Furthermore, the drafts  33 . 3 ,  34 . 3 , when compared to plane-parallel contact surfaces, reduce the risk of soil jamming between the carrier part  22  and the crosspieces  33 ,  34 , and hindering disassembly of the guide element  30 . The clearances  35 . 1 ,  35 . 2 , accommodate the edges of the carrier part  22 . This ensures that the guide element  30  abuts with its entire abutment surface  32 . 3  on the front side  24  of the carrier part  22  even if there are manufacturing tolerances or a manufacturing-related burr on the edges of the carrier part  22 . 
         [0068]      FIG. 5  shows the guide element  30  and the tine  20  in a connection region  30 . 3  of the guide element  30  in a first embodiment in a sectional view extending in a direction transverse to the longitudinal extension of the guide element. The section runs along the cutting line indicated by V in  FIG. 2 . 
         [0069]    The guide element  30  thus also abuts on a front side  24  of the carrier part  22  of the tine  20  with its back side  32 . 3  in a connection region  30 . 3  facing the tine  20 . In the illustrated embodiment, the back side  32 . 3  is designed flat transversely to the longitudinal extension of the guide element  30 . The guide element  30 , designed as shown in  FIG. 5  in its connection region, may be designed as shown in  FIG. 3  in its opposite end region  30 . 1  or, in accordance with the embodiment shown in  FIG. 4 , with crosspieces  33 ,  34 . 
         [0070]    Compared to the smallest thickness  38 . 1  in the end region  30 . 1  of the guide element  30  shown in  FIGS. 3 and 4 , the greatest thickness  38 . 2  of the guide element  30  is provided in the connection region  30 . 3 , as indicated by the different lengths of the double arrows. Thus, in the region of the greatest mechanical load, and therefore the greatest abrasion of the guide element  30 , the thickness  38 . 2  is greatest while the smallest thickness  38 . 1  is provided in the area of the lowest mechanical load and least abrasion. 
         [0071]      FIG. 6  shows the guide element  30  and the tine  20  in a connection region  30 . 3  of the guide element  30  in a first embodiment in a sectional view extending in a direction transverse to the longitudinal extension of the guide element. The course of the section corresponds to that in  FIG. 5 . 
         [0072]    As already described in  FIG. 4  for the end region  30 . 1  of the guide element  30 , crosspieces  36 ,  37 , are provided in the connection region  30 . 3  of the guide element  30 , to the side of the carrier  22  of the tine  20 , in the embodiment shown in  FIG. 6 . A guide receptacle  32 . 4  for the carrier part  22  is formed between the crosspieces  36 ,  37 . The crosspieces  36 ,  37 , have outer crosspiece surfaces  36 . 1 ,  37 . 1 , which transition into obliquely tapering drafts  36 . 3 ,  37 . 3 , via rounded transitions  36 . 2 ,  37 . 2 . The drafts  36 . 3 ,  37 . 3  are transitioned into the contact surface  32 . 3 , extending in a plane to the back side  32 . 2  of the guide element  30 , via clearances  35 . 3 ,  35 . 4 . 
         [0073]    The function of the crosspieces  36 ,  37 , with their radial transitions  36 . 2 ,  37 . 2 , drafts  36 . 3 ,  37 . 3 , and  35 . 3 , and clearances  35 . 4 , corresponds to the function described for the end region  30 . 1  in  FIG. 4 . Again, there is lateral guiding of the guide element  30  in the guide receptacle  32 . 4  on the carrier part  22  of the tine  20 , along with the described advantages. The guide element  30 , designed as shown in  FIG. 6  in its connection region, may be designed as shown in  FIG. 3  in its opposite end region  30 . 1  or, in accordance with the embodiment shown in  FIG. 4 , with crosspieces  33 ,  34 . If the guide element  30  is designed with crosspieces  33 ,  34 ,  36 ,  37 , in both, its end region  30 . 1 , as shown in  FIG. 4 , and in its end region  30 . 3 , as shown in  FIG. 6 , high transverse forces acting on the guide element  30  can be absorbed. By means of the crosspieces  36 ,  37 , in the connecting region, mounting of the guide element  30  on the carrier part  22  of the tine  20  is significantly facilitated since the guide element  30  aligns itself laterally relative to the carrier part  22  due to the crosspieces  36 ,  37 , so that the first screw receptacle  31  is flush with the first bore  23 . 1 . 
         [0074]    As already described with reference to  FIG. 5 , the greatest thickness  38 . 2  of the guide element  30 , indicated by a double arrow, is provided in the connection region  30 . 3 , which continuously decreases over the central region  30 . 2  toward the end region  30 . 1  of the guide element  30 . 
         [0075]      FIG. 7  shows a detail of the lateral sectional view, shown in  FIG. 2 , in the region of a form-fitting connection. The section shown is indicated by a circle labeled VII in  FIG. 2 . The same components are designated as already described for  FIGS. 1 and 2 . 
         [0076]    The guide element  30  has a first plug attachment  70  which is molded on as an extension of the guide element  30  at its connection region  30 . 3 . The first plug attachment  70  is reduced in thickness when compared to the connection region  30 . 3  and arranged such that it forms a continuous back side  32 . 2  with the other regions of the guide element  30 , with the first plug attachment  70  abutting against the carrier part  22  of the tine  20 . The first plug attachment  70  is formed as a planar element with a recess  73 . At its free end, the first plug attachment  70  is terminated by a bridge  72  with a rounded front edge  76 , sloping down towards the tine  20  in the direction of the connection region  30 . 3  of the guide element  30 . 
         [0077]    At its end facing the guide element  30 , the share tip  40  has a first receptacle  80 , which is covered by a first covering portion  81  in the tool feed direction V. The first plug attachment  70  is held in the first receptacle  80  by a form-fitting connection. For this purpose, a molded-on attachment  82  is provided on a bottom side  81 . 1  of the first covering portion  81  facing the receptacle  80 . The molded-on attachment  82  is formed such that it is fitted into the recess  73  of the first plug attachment  70  in a form-fitting manner. The second fastening screw  13  is inserted through the molded-on attachment  82 . 
         [0078]    The first covering portion  81  abuts on a top side  70 . 1  of the first plug attachment  70  with its bottom side  81 . 1 . In the transition from the bottom side  81 . 1  to the molded-on attachment  82 , a clearance groove  81 . 2  is provided circumferentially to the molded-on attachment  82 , in which the edges of the first plug attachment  70 , extending circumferentially around the recess  73  are accommodated. 
         [0079]    Extending from the first plug attachment  73 , the guide element  30  has a front surface  39  which is arranged at a small distance from a terminating edge  49  of the share tip  40 . 
         [0080]    One locking attachment  12 . 2 ,  13 . 2 ,  14 . 2 , each is molded on the fastening screws  12 ,  13 ,  14 , adjacent to their screw head  12 . 1 ,  13 . 1 ,  14 . 1 . The locking attachments  12 . 2 ,  13 . 2 ,  14 . 2 , engage with screw locks  31 . 1 ,  42 . 1 ,  43 . 1 , which are provided on the respective screw receptacles  31 ,  42 ,  43 , facing the carrier part  22 . The fastening screws  12 ,  13 ,  14 , are thus secured against rotation. 
         [0081]    The carrier part  22  has bores  25 . 1 ,  25 . 2 , extending transversely to the tool feed direction V, to which optional blade wing, not shown, may be bolted. 
         [0082]    To assemble the cultivator share  10 , the guide element  30  is so aligned to the tines such that its first screw receptacle  31  is flush with the first bore  23 . 1  in the carrier part  22  of the tine  20 . Next, the first fastening screw  12  is inserted through the first screw receptacle  31  and the first bore  23 . 1  bolted to the tine  20  on the rear, using the first screw nut  12 . 3 , as shown in  FIG. 2 . In this case, the first fastening screw  12  is secured against rotation by the first locking attachment  12 . 2  in the first screw lock  31 . 1  so that no tools are required on the side of the first screw head  12 . 1  for tightening. The guide element  30  is thus affixed to the carrier part  22  of the tine  20  by the first screw connection  11 . 1  that is formed. 
         [0083]    In a second assembly step, the share tip  40  is placed against the carrier part  22  of the tine  20  such that the molded-on attachment  82  of the first receptacle  80  engages with the recess  73  of the first plug attachment  70  of the guide element  30 . The share tip  40  is thus oriented with respect to the carrier part  22  so that the second screw receptacle  42  of the share tip  40  is flush with the second bore  23 . 2  of the carrier part  22  and the third screw receptacle  43  of the share tip  40  is flush with the third bore  23 . 3  of the carrier part  22 . Again, the second and third fastening screw  13 ,  14 , are inserted and bolted on the rear. The fastening screws  13 ,  14 , are thus secured against rotation by their locking attachments  13 . 2 ,  14 . 2 , in the screw locks  42 . 1 ,  43 . 1  of the screw receptacle  42 ,  43 , so that the rear screw nuts  13 . 3 ,  14 . 3 , can be tightened. The share tip  40  is mounted on the carrier part  22  of the tine  20  by means of the thus formed second and third screw connection  11 . 2 ,  11 . 3 . 
         [0084]    The molded-on attachment  82  of the first receptacle  80  and the recess  73  of the first plug attachment  70  form a form-fitting connection which blocks a movement of the guide element  30  out of the first receptacle  80 , in addition to the screw connections  11 . 1 ,  11 . 2 ,  11 . 3 . In the tool feed direction V, movement of the guide element  30  is blocked by the abutment of the first plug attachment  70  with its top side  70 . 1  at the bottom side  81 . 1  of the first covering portion  81 . The guide element  30  is thus affixed in the first receptacle  80  of the share tip  40  in a form-fitting manner. The form-fitting connection is protected from passing soil by the first covering portion  81 . Damage to the form-fitting connection, for example, by deformation of the first plug attachment  70 , can thus be safely avoided. The share tip  40  and the guide element  30  can therefore be separated easily and quickly even after a long operating time with high wear. This is also facilitated by the small distance between the front surface  39  of the guide element  30  and the terminating edge  49  of the share tip  40 , assuring that no large quantity of soil enters in the region of the form-fitting connection. By means of the second screw connection  11 . 2 , the share tip  40  and the guide element  30  are firmly pressed together and held in this position in the region of the first receptacle  80  and the first plug attachment  70 . Thus, bending open of the first covering portion  81  and the first plug attachment  70  is avoided. This also ensures that the share tip  40  and the guide element  30  can be separated simply and safely even after heavy use. 
         [0085]    The form-fitting connection is designed such that only a suitably formed first plug attachment  70  can be inserted into the first receptacle  80  and be affixed therein. This allows for encoding so that only guide elements  30  and share tips  40  that are matched to one another can be put together. This can ensure, for example, that only guide elements  30  can be fitted with a share tip  40  that have a greatest thickness  38 . 2  in their connection region  30 . 3  that is matched to the share tip  40 . For comparable share tips  40  having a different thickness, other guide elements  30  are respectively provided with a different matching largest thickness  38 . 2 . These can then have differently shaped plug attachments  90 ,  110 , as shown in  FIGS. 9, 10 and 11 , with which they can be affixed in corresponding receptacles  100 ,  120 , of the share tips  40 . 
         [0086]      FIG. 8  shows the section of the form-fitting connection, shown in  FIG. 7 , in a partially sectioned rear view. Here, the carrier part  22  of the tine  20  is marked as a section, corresponding to a section line, marked with VIII in  FIG. 2 . The first plug attachment  70  is inserted into the first receptacle  80  where it is affixed. 
         [0087]    The first receptacle  80  is pocket-shaped and molded into the back side of the share tip  40 . It has insertion chamfers  83 , laterally adjacent to the first covering portion  81 , shown in  FIG. 7 . The first insertion chamfers  83  are here placed in a V-shape with respect to each other, for example, with a 60° opening angle. In the region below the first insertion chamfers  83 , blocking pieces  84  are arranged spaced apart. The two blocking pieces  84  are integrally connected to each other via a connecting piece  85  of the first receptacle  80 . The first insertion chamfers  83 , the blocking pieces  84 , and the connecting piece  62 . 3  form side walls of the first receptacle  80 , which rise from the first covering portion  81 . On the front face, towards the guide element  30 , the first receptacle  80  is opened by a receptacle opening. A release groove can be provided in the first covering portion  81  along the first insertion chamfers  83 , the blocking pieces  84 , and the connecting piece  85 . The release groove forms a rounded transition from the first covering portion  81  to the side walls, reducing tension peaks applied by external forces, compared to a sharp edging. The release groove also serves to receive a burr, as may be present for manufacturing reasons at the edges on the first plug attachment  70  of the guide element  30 , held in the receptacle  80 . 
         [0088]    The first plug attachment  70  is formed as an approximately U-shaped bracket which is connected to the terminal region  30 . 3  of the guide element  30 . It tapers transversely to the tool feed direction V by two first guide surfaces  74 , V-shaped at an angle between, toward two spaced apart opposite side parts  71 , which are connected to the bridge  72  at the front end of the guide element  30 . With the side parts  71 , the bridge  72  and the base body of the first plug attachment  70 , opposite the bridge, the recess  73  of the plug attachment  70  is enclosed. The first guide surfaces  74  transition into contact surfaces  75  of the two side parts  71 . At the end of the first plug attachment  70 , the bracket  72  forms a front edge  76 . The first guide surfaces  74 , the side parts  71 , and the front edge  76  form outer side walls of the first plug attachment  70 . 
         [0089]    In the illustrated assembled state, the first guide surfaces  74  are arranged at a small distance from the first insertion chamfers  83 , the contact surfaces  75  are arranged at a small distance from the first blocking pieces  84 , and the front edge  76  is arranged at a small distance from the connecting piece  85 . The guide element  30  is thus disposed on the side and held rotationally affixed in the first receptacle  80  of the share tip  40 . At the same time, the molded-on attachment  82  engages with the recess  73 , ensuring a form-fitting blocking between the first plug attachment  70  and the first receptacle  80 . This prevents the first plug attachment  70  from sliding out of the first receptacle  80 . 
         [0090]    The first insertion chamfers  83  and the associated first guide surfaces  74  facilitate joining of the share tip  40  and the guide element  30  during assembly. 
         [0091]      FIG. 9  shows the detail, shown in  FIG. 7 , in a second embodiment of the form-fitting connection. The same components are again designated with the same references. 
         [0092]    The second plug attachment  90  is formed as a short attachment, extending across the width of the guide element  30  and facing the carrier part  22  of the tine  20 . The second plug attachment  90  abuts against the carrier part  22  with its back side  32 . 2 . The second plug attachment  90  is inserted into the second receptacle  100  of the share tip  40 . The second receptacle  100  is covered in the tool feed direction V by a second covering portion  101 . The second plug attachment  90  abuts with a second top side  90 . 1  against a second bottom side  101 . 1  of the second covering portion  101  and is held in the tool feed direction V by the same. At its free end, the second plug attachment  90  is terminated by a second rounded front edge  91 , sloping down towards the tine  20  in the direction of the connection region  30 . 3  of the guide element  30 . The second front edge  91  is held spaced apart from a second contact region  102  of the second receptacle  100 . 
         [0093]    In the illustrated embodiment, the second plug attachment  100  is not connected with the share tip  40  by a form-fitting connection, acting in the direction of the longitudinal extension of the guide element  30 . The guide element  30  can be replaced as required without having to remove the share tip  40  first. The form-fitting connection formed by the second plug attachment  100  and the second covering portion  101  and acting in the direction of the tool feed direction V prevents lifting or bending of the guide element  30  in its connection region  30  and on the second plug attachment  100  itself. Due to the small distance between the terminating edge  49  of the share tip and the front surface  39  of the guide element  30 , larger quantities of soil are prevented from passing into the region of the second receptacle  100  and jamming the components against one another. The share tip  40  and the guide element can therefore be separated easily and safely even after a long operating time with correspondingly high wear. 
         [0094]    Compared to the form-fitting connection shown in  FIGS. 7 and 8 , the respective receptacles  80 ,  100 , and the associated plug attachments  90 ,  110 , are designed differently so that the second plug attachment  110  does not fit into the first receptacle  80  and the first plug attachment  90  does not fit into the second receptacle  100 . This can allow for an unambiguous assignment of a particular embodiment of a share tip  40  to a corresponding embodiment of a guide element  30 . For example, different embodiments of share tips  40  with different material thicknesses in their region facing the guide element  30  can be uniquely matched to associated guide elements  30  with matched greatest thicknesses  38 . 2  in their connection region  30 . 3 . Guide elements  30  with a different greatest thickness  38 . 2  cannot be erroneously combined with a non-associated share tip  40 , due to the design of their plug attachment  70 ,  90 . This ensures that there are no edges in the region of transition between the share tip  40  and the guide element  30 , which are subject to increased wear. Furthermore, it is ensured that the share tip  40  and the guide element  30  have similar service lives so that the maintenance intervals are matched. 
         [0095]      FIG. 10  shows the section, shown in  FIG. 9 , in a Partially sectioned rear view. 
         [0096]    The second plug attachment  90  is inserted into the second receptacle  100  of the share tip  40 . Due to the small distance between the second front edge  91  of the guide element  30  and the opposite second contact region  102  of the share tip  40  soil is prevented from entering into the second receptacle  100 . 
         [0097]    The second plug attachment  90  is formed over the entire width of the guide element  30  so that a resilient form-fitting connection is formed in the tool feed direction V. Transversely to the tool feed direction V, the form-fitting connection is not effective. The form-fitting connection also does not block movement of the second plug attachment  90  from the second receptacle in the direction of the guide element  30 . 
         [0098]    As shown with reference to  FIG. 6 , opposed crosspieces  36 ,  37 , are arranged to the side of the tine  20  laterally affixing the guide element  30 . In combination with the form-fitting connection, formed by the second plug attachment  90  and the second receptacle  100  and acting in the tool feed direction V, the guide element is thus held in the tool feed direction V, as well as transversely thereto, in a form-fitting manner. The second screw connection  11 . 2  prevents the second plug attachment  90  from being pulled out of the second receptacle. For individual disassembly of the guide element  30 , only the second screw connection  11 . 2  needs to be loosened and the guide element  30  with its second plug attachment  90  pulled out of the second receptacle  100 . The share tip  40  can remain mounted. 
         [0099]      FIG. 11  shows the detail, shown in  FIGS. 8 and 10 , in a third embodiment of the form-fitting connection. 
         [0100]    The third plug attachment  110  is formed by two U-shaped attachments  112 , spaced apart and arranged to the side of the tine  20 , which are held in two U-shaped recesses  122  in the correspondingly formed third receptacle  120 . Similarly, to the first plug attachment  70 , the third plug attachment  110  has two V-shaped guide surfaces  111 , extending at an angle, which are arranged opposite two corresponding insertion chamfers  121  of the third receptacle  120 . The side walls of the U-shaped attachments  112  form contact surfaces  113  which are arranged opposite the blocking portions  124  of the third receptacle  120 . A middle crosspiece is formed between the U-shaped recesses  122 , through which the second fastening screw  13  of the second screw connection  11 . 2  is inserted. 
         [0101]    Compared to the form-fitting connection shown in  FIGS. 9 and 10 , formed by the second plug attachment  90  and the second receptacle  100 , the form-fitting connection shown in  FIG. 11  also blocks lateral movement of the guide element  30  or the share tip  40 . Therefore, the crosspieces  36 ,  37 , attached to the side of the tine  20  on the back side  32 . 2  of the connection region  30 . 3  of the guide element  30 , can be omitted. Compared to the form-fitting connection shown in  FIGS. 7 and 8 , which, together with the transversely extending bridge  72 , encloses the molded-on attachment  82 , thus blocking movement of the second plug attachment  90  out of the second receptacle  100 , the form-fitting connection shown in  FIG. 11  acts only in the tool feed direction V and transversely to the longitudinal extension of the guide element  30  and the share tip  40 . In the direction of the longitudinal extension of the guide element  30  and of the share tip  40 , the guide element  30  is held only by the first screw connection  11 . 1  and the share tip  40  is held only by the second and third screw connection  11 . 2 ,  11 . 3 . Accordingly, the share tip  40  does not need be detached from the tine  20  for mounting and dismounting of the guide element  30 . The third plug attachment  110  can be removed from, and pushed into, the third receptacle  120  after the first attachment screw  12  is removed.