Chisel holder

Abstract

The invention relates to a chisel holder (30) for a soil cultivation machine, in particular for a road milling machine, a stabilizer, a recycler, or a surface miner, with a support body (35) which has a chisel receptacle (32) in the area of ​​a working side or at least carries a cutting tip, wherein the support body (35) indirectly or directly carries a plug socket (44) on a plug socket side, wherein the plug socket (44) has a plug socket longitudinal axis (44.2), wherein the plug socket longitudinal axis (44.2) lies in a central longitudinal plane (ME) of the chisel holder (30), wherein the support body (35) has two front planar cutting surfaces (41.1, 41.2) forming a pair of cutting surfaces, which are angled to each other such that they enclose a transverse support angle (α), and which are arranged in a region in front of the plug socket (44), wherein the front cutting surfaces (41.1, 41.2) extend laterally from the plug-in end (44) towards the rear of the chisel holder (30) beyond the plug-in end longitudinal axis (44.2) of the plug-in end (44), and wherein the support body (35) has at least one rear cutting surface (43.1, 43.2) which forms an obtuse longitudinal support angle (β) with at least one of the front cutting surfaces (41.1, 41.2) and which is arranged at least partially behind the plug-in end (44). In order to achieve improved follow-through behavior with such a chisel holder compared to a base on which the chisel holder is mounted, it is provided that the front cutting surfaces (41.1, 41.2) transition laterally to the plug-in end (44) via at least one inclined surface (42.1) directly or indirectly into the rear cutting surface (43.1, 43.2) or into a rear cutting surface (43.1, 43.2).

Description

[0001] The invention relates to a chisel holder for a soil cultivation machine, in particular for a road milling machine, a stabilizer, a recycler, or a surface miner, with a support body which has a chisel receptacle or carries a cutting tip in the area of ​​a working side, wherein the support body indirectly or directly carries a plug socket on a plug socket side, wherein the plug socket has a plug socket longitudinal axis, wherein the plug socket longitudinal axis lies in a central longitudinal plane of the chisel holder, wherein the support body has two front planar cutting surfaces forming a pair of cutting surfaces, which are angled to each other such that they enclose a transverse support angle and which are arranged at least partially in front of the plug socket, wherein the front cutting surfaces extend laterally of the plug socket towards the rear of the chisel holder beyond the plug socket longitudinal axis of the plug socket.and wherein the support body has at least one rear cutting surface which forms an obtuse longitudinal support angle with the front cutting surfaces, and which is arranged at least partially behind the plug-in end.

[0002] In such chisel holders according to the invention, it is particularly possible that the two front cutting surfaces are arranged completely or partially on both sides of the central longitudinal plane. Preferably, the two front cutting surfaces each form the same angle with the central longitudinal plane.

[0003] In the case of chisel holders according to the invention, the central longitudinal plane may run in the direction of the feed direction.

[0004] Preferably, the central longitudinal axis of the chisel holder lies in the central longitudinal plane.

[0005] The removal surfaces of the chisel holders according to the invention can be designed as flat surfaces completely or at least partially.

[0006] In a chisel holder according to the invention, the insertion point is arranged in the area of ​​the underside of the chisel holder. Opposite this, the chisel holder forms its upper side on its machining side. When the chisel holder is used as intended, the front side is located at the front of the chisel holder in the feed direction, and the back side is located at the rear of the chisel holder in the feed direction.

[0007] In a chisel holder according to the invention, its central longitudinal plane can be the plane that encloses the central longitudinal axis of the chisel receptacle as well as the longitudinal axis of the shank. Preferably, the bearing surface formed by the chisel receptacle is perpendicular to the central longitudinal plane.

[0008] In a chisel holder according to the invention, the central longitudinal plane can preferably form a plane of symmetry of the chisel holder, at least for partial areas. This means, in particular, that the functional surfaces or functional components of the chisel holder described below are designed symmetrically relative to the central longitudinal plane.

[0009] Functional surfaces or functional components here refer to surfaces or components that are essential for the function of the chisel holder and its fixation in the corresponding lower part; these are in particular the functional surfaces and functional components explained in more detail in the following application text: - Front and / or rear wear surfaces - inclined surfaces - front and / or rear stock mounting surface - Shaft widening - Chisel holder, as well as the associated support section and the bearing surface - Screw pressure surface - Ejector socket - and / or cylinder section

[0010] Particularly advantageous are not only the functional surfaces and functional components formed on the support body, but also the fact that the entire support body is designed symmetrically to the central longitudinal plane.

[0011] It is also preferred that not only the functional surfaces and functional components formed at the plug-in connection, but the entire plug-in connection is symmetrical to the central longitudinal plane.

[0012] The symmetrical design allows for simple manufacturing, for example by forging, and ensures that the tool holders can be interchanged at any mounting location on the milling drum. Furthermore, with regard to the functional surfaces and components exposed during operation, this results in predictable and consistent wear behavior independent of the mounting location.

[0013] In such chisel holders according to the invention, it is particularly possible that the two front cutting surfaces are arranged completely or partially on both sides of the central longitudinal plane. Preferably, the two front cutting surfaces each form the same angle with the central longitudinal plane.

[0014] In the case of chisel holders according to the invention, the central longitudinal plane may run in the direction of the feed direction.

[0015] Preferably, the central longitudinal axis of the chisel holder lies in the central longitudinal plane.

[0016] The removal surfaces of the chisel holders according to the invention can be designed as flat surfaces completely or at least partially.

[0017] From EP 2 729 666 A2, a chisel holder is known which has a support body. The support body has a chisel receptacle on its machining side. A round-shank chisel can be inserted into this chisel receptacle. Furthermore, the support body has a projecting socket on its side facing away from the machining side. Front cutting surfaces are provided in the area in front of the socket, and rear cutting surfaces are provided in the area behind the socket. The front and rear cutting surfaces are arranged in pairs at an angle to each other. The front cutting surfaces form a transverse support angle. The rear cutting surfaces are also arranged at a transverse support angle to each other. The chisel holder can be inserted into a socket of a base part with its socket in the direction of the socket's longitudinal axis.The cutting motion is limited by the front and rear cutting surfaces, which abut corresponding counter-surfaces of the lower part. A pressure screw is used to fix the chisel holder in the lower part; this screw acts on a pressure surface of the socket.

[0018] During operation, the cutting surfaces of the chisel holder and / or the corresponding mating surfaces of the base wear down. This causes the chisel holder to settle relative to the base in the direction of the longitudinal axis of the shank. To facilitate this, EP 2 729 666 A2 provides a recessed space in the base in the edge area where the front cutting surfaces meet the rear cutting surfaces.

[0019] The object of the invention is to provide a chisel holder of the type mentioned above which enables improved tracking behavior of the chisel holder during operation.

[0020] The object of the invention is achieved by the front removal surfaces transitioning at least partially laterally to the plug-in insertion via at least one inclined surface, either directly or indirectly, into the rear removal surface or into one of the rear removal surfaces.

[0021] Due to the use of the inclined surfaces, the available insertion path in the direction of the plug-in longitudinal axis increases, while the insertion space in the lower part remains constant. This increases the service life of the lower part until the inclined surface comes into contact with it. Consequently, the lower part can be replaced later. This represents a significant economic advantage.

[0022] Typically, the chisel holder is mounted in a base, which is rigidly connected to a milling drum. The chisel holder frequently needs to be replaced when it reaches the end of its service life. This requires loosening the fastener that holds the chisel holder in the base. The chisel holder is then removed from the base, which can be difficult in the harsh conditions of a construction site, especially in confined spaces. A new chisel holder then needs to be mounted and attached to the base. The longer service life of the preferred embodiment of the invention not only simplifies and extends the replacement intervals, but ultimately also allows the chisel holder to be used for a longer period. In particular, this significantly postpones the time-consuming replacement of the base, which is welded to the milling drum.

[0023] As an alternative to extending tool life, a more compact design can be achieved while maintaining the same repositioning distance compared to the base. In particular, the height by which the tool holder protrudes above the base can be reduced. Consequently, the overhang of the tool holder or cutting tip above the base is also reduced. This decreases the torque transmitted during machining, thus reducing the machining forces acting on the tool holder or cutting tip. As a result, internal stresses in both the tool holder and the base can be reduced, leading to improved overall system stability.

[0024] One possible embodiment of the invention is such that the inclined surfaces extend in the area between two transverse edges, with the front transverse edge facing the front of the chisel holder forming a transition between the front cutting surface and the inclined surface, and the rear transverse edge facing the rear of the chisel holder forming a transition between the inclined surface and the associated rear cutting surface. This results in a simple geometry that can be manufactured with minimal effort. It can also preferably be provided that the maximum distance between the two transverse edges, measured parallel to the central longitudinal plane and perpendicular to the longitudinal axis of the insertion element, is smaller than the extent of the insertion element, measured parallel to the central longitudinal plane and perpendicular to the longitudinal axis of the insertion element.In this way, the front and rear removal surfaces can be adequately dimensioned, and a sufficiently large after-surface area remains.

[0025] Preferably, the two transverse edges should run parallel to each other.

[0026] It is particularly preferred that the maximum distance between the two transverse edges, measured parallel to the central longitudinal plane and perpendicular to the longitudinal axis of the plug-in insertion, is less than 0.7 times, or preferably less than 0.6 times, the extension of the plug-in insertion, measured in the central longitudinal plane and perpendicular to the longitudinal axis of the plug-in insertion, in order to avoid an excessively wide clearance in the lower part in the direction parallel to the central longitudinal plane. This has proven particularly suitable for road milling applications.

[0027] Preferably, the minimum distance between the two transverse edges, measured parallel to the central longitudinal plane and perpendicular to the plug-in insertion longitudinal axis, is greater than the measure of 0.2 times the extension of the plug-in insertion, measured in the central longitudinal plane and perpendicular to the plug-in insertion longitudinal axis.

[0028] If both transverse edges of the inclined surfaces are designed to run at an angle of less than 90°, preferably less than 70°, from the front of the chisel holder to the rear of the chisel holder and inclined to the central longitudinal plane, then the front cutting surfaces can be extended further outwards towards the rear of the chisel holder in a load-optimized manner. Furthermore, this angle of the transverse edges makes it more difficult for waste material to penetrate into the area of ​​the after-cutting chamber.

[0029] Preferably, the inclined surfaces are designed as flat surfaces, at least in some areas. They can then be easily manufactured, for example by milling.

[0030] If it is intended that the inclined surfaces form an obtuse angle with both the associated front and rear cut-off surfaces, then load peaks in the area of ​​the inclined surface are reduced.

[0031] Preferably, the angle formed by the inclined surfaces and their associated front cutting surface is selected to be between 140° and 165°. Additionally or alternatively, the angle between the inclined surface and the rear cutting surface may also be selected to be between 140° and 165°. Preferably, the inclined surfaces form the same angle with both their respective front and rear cutting surfaces.

[0032] For reasons of symmetry, it is preferred if the two inclined surfaces are designed symmetrically to the central longitudinal plane of the chisel holder. The front and rear cutting surfaces are also particularly preferred to be symmetrical to the central longitudinal plane.

[0033] For a chisel holder that is symmetrical or substantially symmetrical with respect to the central longitudinal plane, it is advantageous to provide an inclined surface on each side of the insertion point, which directly or indirectly transitions the associated front cutting surface into a rear cutting surface, with the two rear cutting surfaces lying in the same plane or arranged at an angle to each other. Naturally, this measure is not limited to symmetrical or substantially symmetrical chisel holders.

[0034] One possible embodiment of the invention is such that the inclined surfaces, viewed along the longitudinal axis of the insertion point, are arranged in a V-shape on the underside of the chisel holder, diverging from the front of the chisel holder towards the rear and / or from the underside of the chisel holder towards the top. The arrangement can be chosen to allow for the greatest possible extension travel. Preferably, this does not adversely affect the stability of the chisel holder.

[0035] A particularly preferred embodiment of the invention is such that the plug-in end at its end facing the support body transitions directly or indirectly into the support body by means of a shaft extension, that the shaft extension with widening sides extends laterally to both sides of the plug-in end and widens the cross-section of the plug-in end in these areas towards the support body and radially to the longitudinal axis of the plug-in end, and that the extension of the widening sides in the direction of the longitudinal axis of the plug-in end is at least 5%, preferably at least 10%, and particularly preferably at least 14% of the length of the plug-in end in this direction in at least one area. This significantly increases the lateral stability of the chisel holder.

[0036] It has proven particularly advantageous if the widening sides of the shaft widening are designed to extend over the entire depth of the insertion point parallel to the central longitudinal plane, or at least over 50% of the depth of the insertion point.

[0037] In the event of an overload, the chisel holder can be subjected to considerable stress in the transition area between the socket and the support body. This stress can be absorbed by the shank extension. However, if a particularly intense overload occurs, the chisel holder deforms. To prevent plastic deformation of the system, a further embodiment of the invention provides that the shank extension forms a rear shank support, wherein the rear shank support has two spaced-apart side contact surfaces that are connected to each other directly or indirectly by means of an overload support surface. In the described overload situation, the side contact surfaces and the overload support surface provide additional support points for transferring the load to the lower part. Preferably, the side contact surfaces come into contact with the lower part first.If this is insufficient, the overload contact surface then engages with the lower part, resulting in a kind of staggered overload protection. Alternatively, in the event of an overload, the overload contact surface may initially engage with the lower part. Subsequently, if the chisel holder and / or the lower part deforms, the side contact surfaces can then engage with the lower part.

[0038] By positioning the overload contact surface on the shaft extension, a larger transmission area can be achieved to dissipate forces in the event of an overload. This reduces the surface pressures and results in lower overall stresses in the larger cross-section of the shaft extension.

[0039] This more robust design is particularly suitable in conjunction with the undercut fixing of the plug-in end in the socket described below. This stable fastening of the plug-in end in the socket now generates significantly higher forces in the transition area between the plug-in end and the support body of the chisel holder.

[0040] In this context, it can also be provided that the side contact surfaces are designed as flat surfaces and are angled relative to each other in a V-shape, particularly at an angle to one another. In the event of overload, the V-shaped side contact surfaces bear against the lower part. Due to their angle, a spring-like preload is created in the chisel holder and / or the lower part in the event of overload, which at least partially relieves the stress in the component.

[0041] It has been shown that a suitable angle of attack for the side contact surfaces is found in the range between 45° and 100°. An angle between 50° and 90° is particularly preferred. For use with road milling machines, an angle of attack in the range between 66° and 76° is especially suitable.

[0042] Preferably, the (virtual or actual) extension of at least one of the transverse edges bounding the inclined surfaces, preferably both transverse edges, intersects the associated side contact surface of the chisel holder, so that the front cutting surfaces can be brought close to the rear shank contact.

[0043] Preferably, at least one of the transverse edges or an extension of at least one transverse edge is arranged perpendicular to the associated side contact surfaces.

[0044] The object of the invention is also achieved with a tool system comprising a chisel holder according to one of claims 1 to 12 and a lower part wherein the chisel holder is attached with its plug-in end in a plug-in receptacle of the lower part, and wherein the two inclined surfaces of the chisel holder are spaced apart from the lower part in the area of ​​recesses of the lower part, each forming a recess space opposite the lower part.

[0045] In particular, the recesses may be designed as trough-shaped depressions. Preferably, the distance between the transverse edges bounding the inclined surfaces is smaller than the width of the trough-shaped depression in the direction parallel to the central longitudinal plane, so that the transverse edges do not contact the front and / or rear support surfaces of the lower part against which the front and / or rear cutting surfaces of the chisel holder rest. This prevents the transverse edges from digging into the front or rear support surface in an undesirable manner.

[0046] In other words, it can also be provided that the front and / or rear cutting surfaces extend into the area of ​​the recesses, preferably being provided that at least one of the transverse edges that define the inclined surfaces is spaced apart from the lower part in the area of ​​the respective associated recess.

[0047] The invention will be explained in more detail below with reference to an embodiment illustrated in the drawings. The drawings show: Fig. 1. Side view of a tool system with a base and a chisel holder, Fig. 2 the tool system according to Fig. 1 in a perspective view from behind, Fig. 3 the tool system according to the Fig. 1 and Fig. 2 in the Fig. 1 opposite side view, Fig. 4 the tool system according to the Fig. 1-3 in perspective view from the front, Fig. 5 a chisel holder in perspective front view, Fig. 6 the chisel holder according to Fig. 5 in combination with a pressure screw and in perspective side view, Fig. 7. the chisel holder according to the Fig. 5 and Fig. 6 in perspective view from below, Fig. 8. Attach the chisel holder according to the instructions. Fig. 5-7 in a sectional view, Fig. 9 the chisel holder according to the Fig. 5-8 in longitudinal section along its central longitudinal plane, Fig. 10 the lower part of the tool system according to the Fig. 1-4 in perspective side view, Fig. 11 the lower part according to Fig. 10 in perspective view from behind, Fig. 12 the tool system according to the Fig. 1-4 in longitudinal section, Fig. 13 the tool system according to the Fig. 1-4 along the in Fig. 3 with section line shown XIII-XIII, Fig. 14 another representation of the chisel holder according to the Fig. 5-9 in view from below and Fig. 15 a cut along the in Fig. 6. Cutting path marked XV-XV, which runs perpendicular to the longitudinal axis of the plug insertion.

[0048] Fig. Figure 1 shows a tool system with a base 10 and a chisel holder 30 attached to it.

[0049] The lower part 10 has a connection side 11, which may have a contact surface, preferably concavely curved. By means of this connection side 11, the lower part 10 can be placed on the convex outer surface of a (not shown) milling drum tube and suitably fastened to it, for example by means of a weld.

[0050] The lower part 10 may be provided with lateral recesses 12 in the transition area to the connection side 11. These recesses 12 can be used to receive welding material to form a tack weld.

[0051] The base body 13 of the lower part 10 forms the lower connection side 11. This base body 13 has a front face 13.1 facing forward in the feed direction V and a rear face 13.2 facing backward in the feed direction V. The lower part 10 is bounded laterally by side surfaces. The feed direction V runs in Fig. 1 from left to right. This feed direction V results from the intended use of the chisel holder 30 or the tool system.

[0052] It may be provided that at least one paragraph 13.3 is present in the area of ​​at least one of the side surfaces in order to form a material drainage area.

[0053] According to the Fig. It is possible that the lower part 10 has a holder receptacle 14. The holder receptacle 14 has front support surfaces 15.1, 15.2, which are arranged at least partially in front of a plug receptacle 18. The plug receptacle 18 can be provided as a through-hole or as a recess in the base body 13 of the lower part 10.

[0054] Preferably, a recess 15.3 is arranged between the two front support surfaces 15.1, 15.2 in the area in front of the plug receptacle 18. The two front support surfaces 15.1, 15.2 are arranged at an angle to each other, as is particularly evident Fig. 11. This angle opens towards the top of the lower part 10.

[0055] It is also possible that the lower part 10 has at least one rear support surface 16.1, 16.2 in its area facing the rear side 13.2. In the present embodiment, two rear support surfaces 16.1, 16.2 are used. The rear support surfaces 16.1, 16.2 are aligned with each other, so that they are arranged on the same plane. However, it is also conceivable that the two rear support surfaces 16.1, 16.2 are at an angle to each other, preferably forming an obtuse angle.

[0056] The two rear support surfaces 16.1, 16.2 are each formed by support sections 19.3. The support sections 19.3 may form parts of a projection 19.2. Preferably, the two projections 19.2, each forming a support section 19.3, are spaced apart from each other transversely to the feed direction V.

[0057] Fig. Figure 10 illustrates that the two rear support surfaces 16.1, 16.2 can also be connected to each other by a transition section 16.3. It is possible that the transition section 16.3 is then also used to support the chisel holder 30.

[0058] Evidentiously Fig. On both sides of the lower part 10, a front support surface 15.1, 15.2 transitions into a rear support surface 16.1, 16.2. Advantageously, recesses 17, which can be groove-like, are provided between the front support surfaces 15.1, 15.2 and the associated rear support surfaces 16.1, 16.2. Thus, the front support surfaces 15.1, 15.2 are spatially separated from the rear support surfaces 16.1, 16.2 to form defined support areas.

[0059] Fig. Figure 10 shows that the socket 18 can be equipped with an insertion extension 18.1 at its upper end. This insertion extension serves to facilitate the insertion of a plug-in end 44 of the chisel holder 30 (see Figure 10). Fig. 5).

[0060] An overload support area 18.4 can be provided in the area of ​​the plug receptacle 18. This overload support area 18.4 preferably has two clamping surfaces 18.5, 18.6, which are arranged at an angle to each other. The two laterally arranged clamping surfaces 18.5, 18.6 can be connected by means of a locking surface 18.7. The locking surface 18.7 also extends at an angle to the clamping surfaces 18.5, 18.6. Preferably, each clamping surface 18.5, 18.6 forms the same angle with the locking surface 18.7, which is preferably obtuse.

[0061] With the chisel holder 30 mounted, at least a part of the functional surfaces and functional sections of the lower part 10, in particular the clamping surfaces 18.5, 18.6, the front support surfaces 15.1 15.2, the rear support surfaces 16.1, 16.2, the insertion extension 18.1 and / or the shank support surface 18.2 described below, can be arranged symmetrically to a central longitudinal plane ME of the chisel holder 30.

[0062] Preferably, the overload support area 18.4 with its clamping surfaces 18.5 and 18.6 and the securing surface 18.7 is formed by the insertion extension 18.1, or is arranged in the area of ​​the insertion extension 18.1, in order to achieve a compact design.

[0063] The Fig. 10 and Fig. Figure 11 further shows that a front shaft support surface 18.2 facing the front face 13.1 is formed within the socket 18. The front shaft support surface 18.2 may be interrupted by a recess 18.3, so that partial surfaces of the front shaft support surface 18.2 are formed on both sides of the recess 18.3. The recess 18.3 may, in particular, be groove-shaped. The recess may extend from the underside, in particular the connection side 11, of the base body 13 in the direction of the longitudinal extent of the socket 18. A shaped element (not shown), in particular a clamping sleeve, a dowel pin, or the like, may be received in the recess 18.3. The shaped element extends partially into the area of ​​the socket 18. This is clearer in Figure 11. Fig. 12 recognizable.

[0064] A screw receptacle 19 is provided on the reverse side of the base body 13 of the lower part 10. A fastening screw, in particular a pressure screw 20, can be screwed into the screw receptacle 19, as shown. Fig. 12 shows.

[0065] Preferably, access to the screw receptacle 19 is protected in the area between the two projections 19.2 (see Fig. 2) It is possible that the screw receptacle 19 is incorporated here into a surface section 19.1 that extends transversely between the two projections 19.2. The projections 19.2 are bounded by boundary surfaces 19.4 facing the screw receptacle 19. This shows Fig. 11.

[0066] The screw receptacle 19 opens into the area of ​​the plug receptacle 18 of the base body 13, as Fig. Figure 12 illustrates this. Preferably, the base body 13 extends to the opening area of ​​the screw receptacle 19 and is Fig. Figure 12 shows a recess 19.5. The recess 19.5 forms a receiving area that is set back from the socket 18. This receiving area facilitates the insertion of the chisel holder 30 into the socket 18.

[0067] Fig. Figures 5 to 8 illustrate the construction of the chisel holder 30. As these illustrations show, the chisel holder 30 has a support body 35.

[0068] As described below, the support body 35 has a tool holder 32 with a central longitudinal axis M on the machining side and a socket 44 with a socket longitudinal axis 44.2 on an opposite socket end. As shown in the exemplary embodiment, the central longitudinal plane ME of the tool holder 30 can be defined by the central longitudinal axis M and the socket axis 44.2.

[0069] A support section 33 is integrally formed on the support body 35 in the area of ​​one machining side. This support section 33 is preferably designed in the form of a projection or may have a projection. The support section 33 forms at least part of the tool holder 32. Preferably, the tool holder 32 is designed as a bore and has the central longitudinal axis M. The central longitudinal axis M of the tool holder 32 is in the Fig. The longitudinal section shown in Figure 9 is clearly visible. Alternatively, a cutting tip MS can also be provided, in particular attached, to the support body 35 on the machining side. This is shown in Figure 9. Fig. 6 is symbolically represented as an alternative with a dotted line.

[0070] At its free end, the support section 33 forms a bearing surface 31, which preferably extends radially to the central longitudinal axis M of the chisel holder 32. The bearing surface 31 is particularly preferably formed circumferentially.

[0071] The support surface 31 serves to support a wear-resistant disc of a (not shown) round-shank chisel. Such a round-shank chisel is inserted with its chisel shank into the chisel holder 32 of the chisel holder 30. The wear-resistant disc is arranged between the support surface 31 and a head of the round-shank chisel and is freely rotatable about the central longitudinal axis M of the chisel holder 32.

[0072] A centering projection 31.1 can be formed in the area of ​​the bearing surface 31. This centering projection 31.1 can, for example, be designed as a circumferential bead. The centering projection 31.1 serves to center the wear protection disc described above on the bearing surface 31. For this purpose, the wear protection disc can be provided with a circumferential groove on its underside, on the side facing the bearing surface 31. The centering projection 31.1 engages in this circumferential groove, while the underside of the wear protection disc rests on the bearing surface 31.

[0073] The support section 33 can be designed with one or more wear markings 33.1. If several wear markings 33.1 are used, they are preferably arranged spaced apart from each other in the direction of the central longitudinal axis M of the chisel receptacle 32, as shown. Fig. 5 can be seen. The wear markings 33.1 can, for example, be designed as grooves that are at least partially circumferential. This also shows Fig. 5.

[0074] The support section 33 is connected to the support body 35 via a transition section 34. Preferably, the transition section 34 widens the support section 33 in the direction of the support body 35, at least in some areas.

[0075] The support body 35 may have a skirt 35.1 on its front side, which is arranged at least partially in front of the support section 33. The skirt 35.1 may be equipped with recesses 35.2 to enable improved material transport and thus better wear resistance of the chisel holder 30.

[0076] For improved stiffness, the support section 33 may be coupled to the support body 35 by means of stiffening struts 35.3. The stiffening struts 35.3 can extend to both sides and / or along the rear side of the support section 33, as shown in the Fig. 4 and Fig. Show 6.

[0077] The chisel holder 30 is bounded by side surfaces 35.4 in the area of ​​its sides, which extend from its front to its rear. The side surfaces 35.4 preferably have frontal chamfers 35.5 to taper the apron 35.1 in an arrow-like shape at the front. This improves material removal during operation. At the front, the support body 35 has a front piece 35.6, which preferably borders the apron 35.1 at the front.

[0078] Evidentiously Fig. 7. The chisel holder 30 may have an ejector receptacle 36 on its rear side. The ejector receptacle 36 preferably has two functions.

[0079] Firstly, the ejector receptacle 36 serves to hold an ejector tool, which provides access to the chisel receptacle 32. Using the ejector tool, a chisel held in the chisel receptacle 32 can then be driven out in the direction of the central longitudinal axis M of the chisel receptacle 32.

[0080] The second function of the ejector receptacle 36 is to remove debris material that has accumulated in the area of ​​the chisel receptacle 32 during operation. This debris material is conveyed radially outwards through the ejector receptacle 36.

[0081] How Fig. Figure 7 further illustrates that the ejector receptacle 36 is bounded by two side surfaces 36.1. Alternatively, the ejector receptacle 36 may be bounded on its top side by a cover section 36.3. Preferably, the ejector receptacle 36 is bounded by both side surfaces 36.1 and by the cover section 36.3.

[0082] Preferably, the deck section 36.3 is arranged parallel to the support surface 31 to achieve an improved discharge effect. This is illustrated. Fig. 9.

[0083] The side surfaces 36.1 of the ejector receptacle 36 can transition into the contour of the chisel receptacle 32 via transition sections 36.2.

[0084] Fig. Figure 7 illustrates that the ejector receptacle 36 extends from an inner opening area 36.4 outwards to the rear of the chisel holder 30 to an ejector passage opening 36.5.

[0085] Fig. Figure 14 illustrates that the width of the ejector receptacle 36 widens, at least in some areas, towards the outside, i.e., towards the ejector passage opening 36.5. Preferably, the width of the ejector receptacle 36 widens continuously. For this purpose, the side surfaces 36.1 may, for example, be arranged at an angle to each other and enclose an opening angle µ. This opening angle µ is preferably in the range between 20° and 45°, more preferably between 25° and 40°, and most preferably between 30° and 35°. Preferably, the central longitudinal plane ME of the chisel holder 30 corresponds to the bisector of the opening angle µ.

[0086] In the area of ​​the end of the ejector receptacle 36 facing the chisel holder 32, the ejector receptacle 36 forms a minimum internal transverse dimension 36.6, and in the area of ​​the ejector passage opening 36.5, a maximum external transverse dimension 36.7. The ratio of the external transverse dimension 36.7 to the internal transverse dimension 36.6 is preferably selected to be in the range between 1.3 and 2.2, more preferably between 1.5 and 2, and most preferably between 1.7 and 1.9. If the chisel holder 30 is used in a road milling application, it has proven advantageous if the external transverse dimension is at least 30 mm.

[0087] According to, among others, the Fig. 9 and Fig. 12. Alternatively or additionally, it may be provided that the ejector receptacle 36 has an exit height hA in the area of ​​the ejector passage opening 36.5 and an entry height hE in the area of ​​the transition of the ejector receptacle 36 into the chisel receptacle 32. The entry height hE and the exit height hA are measured in the direction of the central longitudinal axis M of the chisel receptacle 32. How Fig. As shown in Figure 9, the inlet height and outlet height hE and hA are measured from the deck section 36.3. Preferably, the inlet height hE is greater than the outlet height hA. To achieve good conveying efficiency, it is preferably intended that the ratio of the inlet height hE to the outlet height hA is chosen to be in the range between 0.6 and 0.9.

[0088] Fig. Figure 9 illustrates that the ejector receptacle 36 forms an inlet cross-section EQ in the inner opening area and an outlet cross-section AQ at the ejector passage opening 36.5, wherein the inlet cross-section EQ and the outlet cross-section AQ are each measured perpendicular to the central longitudinal plane ME of the chisel holder 30. Preferably, the ratio of the area of ​​the outlet cross-section AQ to the area of ​​the inlet cross-section EQ is selected to be in the range between 1.0 and 1.5, preferably between 1.0 and 1.4, and most preferably between 1.1 and 1.3.

[0089] As the illustrations show, the chisel holder 30 has the mid-longitudinal plane ME. Fig. Figure 12 shows a longitudinal section through the chisel holder 30 along the central longitudinal plane ME. As the illustration shows, the central longitudinal axis M of the chisel receptacle 32 lies in the central longitudinal plane ME. Additionally, the longitudinal axis 44.2 of the socket 44 may also lie in the central longitudinal plane ME. This is also illustrated in Figure 12. Fig. 12. Preferably, the central longitudinal plane ME runs in the feed direction V.

[0090] As the Fig. 5 and Fig. As shown in Figure 6, the support body 35 has a support section 40 formed on the underside of the chisel holder 30. The support section 40 has two front cutting surfaces 41.1, 41.2. These front cutting surfaces 41.1, 41.2 are arranged on both sides of the central longitudinal plane in the central longitudinal plane of the chisel holder 30. Preferably, as illustrated in the drawings, the front cutting surfaces 41.1, 41.2 are each completely located on their respective side of the chisel holder 30, laterally adjacent to the central longitudinal plane, and do not penetrate the central longitudinal plane.

[0091] It is conceivable that the two front removal surfaces 41.1, 41.2 are connected to each other by means of a secondary surface 42. The secondary surface 42 penetrates the central longitudinal plane ME.

[0092] The front cutting surfaces 41.1, 41.2 enclose a transverse support angle α, as Fig. Figure 5 shows that this angle α should preferably be in the range between 100° and 120°. The angle bisector of this angle α preferably lies in the central longitudinal plane ME.

[0093] As the drawings illustrate, a plug-in extension 44 is arranged on the underside of the chisel holder 30, preferably integrally formed. The front cutting surfaces 41.1, 41.2 are arranged at least partially in the feed direction in front of the plug-in extension 44. This illustrates Fig. 6.

[0094] The support section 40 further comprises at least one rear cutting surface 43.1, 43.2. In the illustrated embodiment, two rear cutting surfaces 43.1, 43.2 are used, which in this embodiment lie in one plane and are spaced apart from each other at least partially perpendicular to the central longitudinal plane ME. The two rear cutting surfaces 43.1, 43.2 are positioned at a longitudinal support angle β relative to the front cutting surface 41.1, 41.2, each associated with one of the sides of the chisel holder 30. The longitudinal support angle β between the front cutting surface 41.1 or 41.2 and the associated rear cutting surface 43.1 or 43.2 is preferably selected in the range between 120° and 160°. The bisector of this angle may be positioned such that it intersects the central longitudinal plane ME.

[0095] Fig. Figure 7 shows that the front removal surfaces 41.1, 41.2 each transition via a sloping surface 42.1 into the rear removal surfaces 43.1, 43.2.

[0096] The inclined surfaces 42.1 may extend in the area between two transverse edges. The front transverse edge facing the front of the chisel holder 30 forms a transition between the front cutting surface 41.1, 41.2 and the inclined surface 42.1. The rear transverse edge facing the back of the chisel holder 30 forms a transition between the inclined surface 42.1 and the associated rear cutting surface 43.1, 43.2. The inclined surfaces 42.1 thus transition directly into the front cutting surfaces 41.1, 41.2 and the rear cutting surfaces 43.1, 43.2, respectively. However, an indirect transition is also conceivable, for example, by means of a rounded transition. According to the Fig. 3 and Fig. 6. It can be the case that the inclined surfaces 42.1 form an obtuse angle with both the associated front cutting surface 41.1, 41.2 and the rear cutting surface 43.1, 43.2; it is particularly preferred that the inclined surfaces form the same angle with the front cutting surfaces 41.1, 41.2 and with the rear cutting surfaces 43.1, 43.2.

[0097] The arrangement of the front and rear removal surfaces 41.1, 41.2, 43.1, 43.2 and the inclined surfaces 42.1 is preferably symmetrical to the central longitudinal plane.

[0098] The plug-in fitting 44 preferably has a cylindrical section 44.5, as Fig. Figure 6 shows that the cylinder section 44.5 can have a front partial cylinder surface 44.3 and / or a rear partial cylinder surface 44.4 directed opposite to the feed direction V.

[0099] Preferably, the maximum distance between the respective two transverse edges of the inclined surfaces 42.1, measured parallel to the central longitudinal plane ME and perpendicular to the plug-in attachment longitudinal axis 44.2, is smaller than the extent of the cylindrical section 44.5 of the plug-in attachment 44, measured parallel to the central longitudinal plane ME. The maximum distance X (see Fig. 15) between the two transverse edges, measured parallel to the central longitudinal plane ME and perpendicular to the plug-in insertion longitudinal axis 44.2 should (see Fig. 15) preferably smaller than 0.7 times, preferably smaller than 0.5 times, the maximum extent maxE of the cylindrical section 44.5 of the plug-in attachment 44, measured parallel to the central longitudinal plane ME and perpendicular to the plug-in attachment longitudinal axis 44.2, as Fig. 15 illustrated.

[0100] The drawings (see in particular) Fig. 7) Illustrate that the two transverse edges of the inclined surfaces 42.1 run at an angle ε <90° in the direction from the front of the chisel holder 30 towards the rear of the chisel holder 30 relative to the central longitudinal plane ME. This is shown in Fig. 7 shown as an example on one of the transverse edges.

[0101] Preferably, the inclined surfaces 42.1 are designed as planar surfaces which extend at an angle ε <90° to the central longitudinal plane ME, wherein the angle ε opens towards the rear of the chisel holder 30 and towards the top of the chisel holder 30, as Fig. Figure 7 shows. Accordingly, it can also be the case that the two inclined surfaces 42.1 are V-shaped to each other in view along the longitudinal axis 44.2 of the plug-in attachment and diverge in the direction from the front of the chisel holder 30 towards the rear (i.e. opposite to the feed direction V) of the chisel holder 30 (see Figure 7). Fig. 14) and / or diverge from the underside of the chisel holder 30 towards the top of the chisel holder 30 (see Fig. 6).

[0102] The insertion point 44 of the chisel holder protrudes from the underside of the chisel holder 30, as for example Fig. Figure 6 shows. Advantageously, the plug-in fitting 44 has a three-part structure. This structure is divided in the direction of the plug-in fitting longitudinal axis 44.2 into a first, lower shaft area, which has a front shaft contact surface 45 and a rear screw pressure surface 47.1, into a second, middle shaft area, which has the cylinder section 44.5, and into a third, upper shaft area, which has a shaft widening 44.1.

[0103] The second middle section is located between the first and third shaft sections.

[0104] Advantageously, the extension of the first, lower shaft area in the direction of the plug-in longitudinal axis 44.2 may be at least 30% of the maximum length of the plug-in section 44 in this direction, in order to ensure, in the assembled state, a stable transmission of the forces of the pressure screw 20 and a stable contact of the shaft contact surface 45 with a shaft support surface 18.2 of a lower part.

[0105] Additionally or alternatively, the extension of the second, middle shaft area in the direction of the plug-in insertion longitudinal axis 44.2 may be at least 10% of the maximum length of the plug-in insertion 44 in this direction to ensure sufficient elongation of the plug-in insertion 44 in the direction of the plug-in insertion longitudinal axis 44.2.

[0106] Additionally or alternatively, the extension of the third, upper shaft area in the direction of the plug-in longitudinal axis 44.2 may be at least 5% of the maximum length of the plug-in shank 44 in this direction in order to achieve good load transfer from the chisel holder 30 to the lower part 10 in the event of overload.

[0107] The rear removal surfaces 43.1, 43.2 are clearly identifiable, at least in some areas, arranged behind the plug-in extension 44 in the feed direction V.

[0108] The plug-in connector 44 transitions into the support body 35 at its end facing the support body 35 via a shaft extension 44.1. The shaft extension 44.1 widens the cross-section of the plug-in connector 44 in the direction towards the support body 35 and radially to the plug-in connector's longitudinal axis 44.2, at least in certain areas. Preferably, the shaft extension 44.1 is formed circumferentially around the plug-in connector 44.

[0109] As the representations according to the Fig. 5 and Fig. As can be seen in Figure 6, the shaft extension 44.1 widens the cross-section of the plug-in connector 44. It may be provided that the shaft extension 44.1 widens the cross-section of the plug-in connector 44 in the area of ​​the two sides that correspond to the side surfaces 35.4. In this case, the shaft extension 44.1 may extend laterally with widening sides to both sides of the plug-in connector 44 from the rear rear area to the front front area of ​​the plug-in connector 44, widening the cross-section of the plug-in connector 44 in these areas towards the support body 35 and radially to the plug-in connector longitudinal axis 44.2. Preferably, the greatest extent LE of the widening sides in the direction of the plug-in insertion longitudinal axis 44.2 is at least 5%, preferably at least 10%, particularly preferably at least 14% of the maximum length LS of the plug-in insertion 44, measured in this direction (see figure). Fig. 6) The maximum length LS of the plug-in attachment 44 extends over the shaft widening 44.1 to the support body 35 and preferably includes the greatest extent LE of the widening sides, as Fig. 6 clearly shows.

[0110] It has proven advantageous if the widening sides of the shaft widening 44.1 extend over at least 50% of the maximum extent maxE of the cylindrical section 44.5 of the plug-in extension 44, which runs parallel to the central longitudinal plane ME and perpendicular to the plug-in extension longitudinal axis; it is particularly preferred that the widening sides of the shaft widening 44.1 extend over the entire depth of the plug-in extension 44, and in particular are formed circumferentially.

[0111] Preferably, or alternatively, the shaft extension 44.1 can also extend the rear area of ​​the plug-in socket 44. Particularly preferred, as shown in the drawings, is that the shaft extension 44.1 is formed circumferentially.

[0112] In the present embodiment, the front wear surfaces 41.1, 41.2 transition via a rounded transition of the shaft extension 44.1 into the extension sides of the shaft extension 44.1, as shown. Fig. Figure 6 shows. The widening sides of the shaft widening 44.1 extend convexly and arcuately to the front end region of the plug socket 44.

[0113] The stock extension 44.1 may form a rear stock support 48. The rear stock support 48 has two side contact surfaces 48.1, which are spaced apart from each other. In particular, the side contact surfaces 48.1 may be angled relative to each other in a V-shape.

[0114] The side mounting surfaces 48.1 of the rear shaft mounting 48 can be shown as Fig. 7 each transition laterally into an associated widening side of the shaft widening 44.1, wherein it is preferably provided that one of the side contact surfaces 48.1 extends at least partially laterally next to one side of the central longitudinal plane ME and the other side contact surface 48.1 extends at least partially laterally next to the opposite side of the central longitudinal plane ME.

[0115] Fig. Figure 6 further illustrates that it is also possible for the inclined surface 42.1 to transition laterally into the shaft widening 44.1 via a rounding transition, in particular via a relief groove 49.

[0116] The support body 35, in particular at least a part of the functional surfaces molded onto the support body 35, the front and / or the rear cutting surface 41.1, 41.2, 43.1 and 43.2 and / or the inclined surfaces 42.1 can transition into the shaft extension 44.1 via a rounded transition. The rounded transition is part of the shaft extension 44.1.

[0117] As the illustrations show, the side contact surfaces 48.1 can enclose an angle in the range between 45° and 100°, preferably between 50° and 90°, particularly preferably between 66° and 76°.

[0118] The angle between the side contact surfaces 48.1 opens, preferably in the direction of the front of the chisel holder 30.

[0119] Fig. Figure 14 shows that each side contact surface 48.1 is arranged completely or partially laterally next to the central longitudinal plane ME, such that each side contact surface 48.1 is assigned to one side of the chisel holder 30. Preferably, the side contact surfaces 48.1 do not penetrate the central longitudinal plane ME, as shown. Fig. Figure 14 shows that in this case, the two side contact surfaces 48.1 are preferably connected to each other directly or indirectly via an overload contact surface 48.2. It is also conceivable that the two side contact surfaces 48.1 are connected to the overload contact surface 48.2 indirectly via a rounded transition 48.3. Preferably, the side contact surfaces 48.1 and the overload contact surface 48.2 each form the same angle and / or the side contact surfaces 48.1 and the overload contact surface 48.2 are symmetrical relative to the central longitudinal plane ME. Preferably, the overload contact surface 48.2 is designed as a flat surface. The side contact surfaces 48.1 can also be designed as flat surfaces.

[0120] The drawings illustrate that the overload support surface 48.2 and / or the side support surfaces 48.1 can at least partially transition into the rear removal surfaces 43.1, 43.2 or the single rear removal surface 43.1, 43.2.

[0121] Fig. Figure 8 illustrates that the plug-in attachment 44 has a shaft section which preferably may have at least a partial cylindrical section 44.5. The cylindrical section 44.5 may have a front partial cylindrical surface 44.3 and / or a rear partial cylindrical surface 44.4 oriented opposite to the feed direction. Preferably, the cylindrical section 44.5 forms an at least partially circumferential cylinder which may be interrupted only by one or more lateral indentations 44.6, as shown. Fig. Figure 8 shows. The cylinder axis of the cylinder section 44.5 preferably aligns with the plug-in longitudinal axis 44.2 and is particularly preferably located in the central longitudinal plane ME.

[0122] Preferably, the cylinder section 44.5 connects to the shaft widening 44.1.

[0123] In a chisel holder 30 according to the invention, the widening sides of the shank widening 44.1 may transition laterally, at least partially, into the front and / or the rear partial cylinder surface 44.3, 44.4 via rounded transitions, and / or the side contact surfaces 48.1 of the rear shank contact 48 transition at least partially into the rear partial cylinder surface 44.4 via rounded transitions, and / or the overload contact surface 48.2, facing away from the support body 35, transitions at least partially into the rear partial cylinder surface 44.4 via a rounded transition.

[0124] In the area of ​​its free end, the plug-in attachment 44 has a front shaft design, as shown by the Fig. 5 and Fig. Figure 6 illustrates this. The front shaft contact surface has a front shaft contact surface 45. Preferably, the front shaft contact surface 45 forms two convex sub-surfaces 45.1, 45.2. The front shaft contact surface 45 and / or at least one of the sub-surfaces 45.1, 45.2 can preferably form a partial cylindrical surface of a cylinder with a contact surface for the cylinder axis Z, as shown, inter alia, in Figure 6. Fig. 8 and Fig. 9 is evident.

[0125] Particularly preferred is the arrangement of the two partial surfaces 45.1, 45.2 spaced apart from each other, with a groove 46 preferably formed in the spaced area. The groove 46 serves to receive the aforementioned shaped element, which is inserted into the recess 18.3 of the lower part 10. This ensures alignment of the chisel holder 30 with respect to the lower part 10 and prevents rotation.

[0126] The groove 46 extends in the direction of the longitudinal extension of the plug-in extension 44 and preferably parallel to the contact cylinder axis Z and / or inclined to the plug-in extension longitudinal axis 44.2. The inclination angle of the groove 46 (in particular of the groove base) relative to the plug-in extension longitudinal axis 44.2 can preferably be selected in the range between 2° and 10°.

[0127] Fig. Figure 8 illustrates that the front convex shaft contact surface 45 with its sub-surfaces 45.1, 45.2 can be arranged in a special way. Fig. Figure 8 illustrates a cross-sectional surface SF of the tool holder 30, formed by a cutting plane SE. The cutting plane SE runs parallel to and at a distance from the central longitudinal plane ME through the tool holder 30. The cutting plane SE intersects at least one of the two front cutting surfaces 41.1, 41.2 of the cutting surface pair and the front shank contact surface 45.

[0128] As the drawing shows, a front cutting edge SK of the cutting surface 41.1, 41.2 and a front cutting edge 45.3 of the front shank contact surface 45 are formed in the cut surface. The front cutting edge 45.3 and the front cutting edge SK enclose an undercut angle γ of at least 103° and at most 114°. Preferably, the undercut angle γ opens towards the front, i.e., in the feed direction V, as Fig. Figure 8 shows the function of this undercut angle γ, which will be explained in more detail later.

[0129] Fig. Figure 8 further illustrates that the projections of the plug-in attachment longitudinal axis 44.2 and the cutting edge 45.3 into the central longitudinal plane ME enclose a shaft angle φ with each other. This shaft angle φ opens towards the free end of the plug-in attachment 44. The shaft angle φ is preferably selected in the range between 2° and 10°.

[0130] Evidentiously Fig. 9. Preferably, the front shaft contact surface 45 forms a partially cylindrical surface. Preferably, the contact cylinder axis Z of the partially cylindrical surface of the front shaft contact surface 45 and the longitudinal axis 44.2 of the plug-in attachment form an angle η that opens towards the free end of the plug-in attachment 44.

[0131] The axis angle η between the contact cylinder axis Z of the semi-cylindrical outer surface of the front shaft contact surface 45 and the plug-in longitudinal axis 44.2 can be selected in the range between 2° and 10° to enable secure anchoring of the plug-in end 44 in the plug receptacle 18 of the lower part 10.

[0132] It should be noted again at this point that the cylinder axis of the cylinder section 44.5 is preferably formed by the longitudinal axis 44.2 of the plug-in attachment. Due to the inclination of the contact cylinder axis Z relative to the longitudinal axis 44.2 of the plug-in attachment, the partially cylindrical outer surface formed by the front shaft contact surface 45 is inclined relative to the cylinder section 44.5 by the axis angle η, preferably in the range between 2° and 10°.

[0133] In the Fig. In the illustrated embodiment 9, it is provided that, particularly for reasons of symmetry, the plug-in longitudinal axis 44.2 of the plug-in attachment 44 and the contact cylinder axis Z of the partially cylindrical outer surface of the front shaft contact surface 45 run in the central longitudinal plane ME.

[0134] A particularly preferred embodiment of a chisel holder 30 according to the invention can be such that the front cutting edge 45.3 of the shank contact surface and the contact cylinder axis Z run parallel to each other and the axis angle η and the shank angle φ thus correspond as Fig. 9 illustrates.

[0135] According to evidence, among others Fig. 8 The plug-in attachment 44 has a screw receptacle 47 on its rear side, which forms a flat screw pressure surface 47.1. The screw pressure surface 47.1 penetrates the central longitudinal plane ME. The plane in which the screw pressure surface 47.1 lies is at a pressure angle σ to the front cutting edge 45.3 or to the contact cylinder axis Z of the cylinder that forms the convex front shaft contact 45. This pressure angle σ is preferably selected in the range between 30° and 45°.

[0136] The Fig. 6 and Fig. Figure 8 shows the spatial arrangement of the pressure screw 20 to the screw receptacle 47 in the assembled state of the chisel holder 30.

[0137] How Fig. As illustrated in Figure 14, a relief groove 49 and / or a rounded transition can be arranged in the transition area between the shaft widening 44.1 and the support section 33 of the support body 35. The geometry formed by the relief groove 49 and / or the rounded transition can at least partially surround the plug-in extension 44. A sealing element (not shown) may be accommodated in this relief groove 49 and / or in the area of ​​the rounded transition, which at least partially surrounds the plug-in extension 44.

[0138] A stress-optimized design is achieved in such a construction when a concave rounded transition of the plug-in connector is provided to guide it into the shaft extension. Additionally or alternatively, the shaft extension can also be provided with a transition geometry featuring a relief groove and / or a rounded edge, through which it transitions into the support body.

[0139] To mount the chisel holder 30 to the base 10, the plug-in extension 44 is inserted with its free end into the plug-in receptacle 18. The insertion extension 18.1 facilitates the insertion of the plug-in extension 44.

[0140] The insertion movement of the plug-in end 44 into the plug-in receptacle 18 is limited by the front support surfaces 15.1, 15.2 and the rear support surfaces 16.1 and 16.2 of the lower part 10. The chisel holder 30 abuts these support surfaces 15.1, 15.2, 16.1, 16.2 with its front cutting surfaces 41.1, 41.2 and its rear cutting surfaces 43.1, 43.2.

[0141] The pressure screw 20 can be screwed into the screw receptacle 19 of the lower part 10. The pressure screw 20 then contacts the screw pressure surface 47.1 of the screw receptacle 47. This draws the chisel holder 30 into the socket 18. While the pressure screw 20 is being tightened, the front shaft contact surface 45 slides along the front shaft support surface 18.2, and the chisel holder 30 is pulled into the socket 18. Once the chisel holder 30 has reached its mounting position, the front cutting surfaces 41.1, 41.2 are pressed onto the front support surfaces 15.1, 15.2, and the rear cutting surfaces 43.1, 43.2 are pressed onto the rear support surfaces 16.1, 16.2. Simultaneously, the front shank support surface 45 is pressed against the front shank support surface 18.2 of the lower part 10. Thus, the chisel holder 30 is securely fixed in the lower part 10.

[0142] The rear shaft assembly 48, with its side contact surfaces 48.1, is positioned at a short distance from the associated clamping surfaces 18.5, 18.6 of the lower part 10. This illustrates Fig. 13. Furthermore, the overload support surface 48.2 is positioned at a distance from the clamping surface 18.7 of the lower part 10. If an overload now acts on the chisel holder 30, the chisel holder 30 is elastically deformed and the side support surfaces 48.1 come into contact with the associated clamping surfaces 18.5, 18.6. Thus, additional support of the chisel holder 30 is achieved.

[0143] If the overload is particularly high, the clamping surfaces 18.5, 18.6 are elastically deformed and deflect outwards towards the corresponding sides of the chisel holder 30. The overload contact surface 48.2 then comes into contact with the clamping surface 18.7. This limits the deflection of the clamping surfaces 18.5, 18.6 to prevent damage to the lower part 10 and to provide an additional support area for distributing the overload.

[0144] After the overload event has ended, the chisel holder 30 returns to its position in Fig. Return to the original position shown in 13.

[0145] In the event of overload, stress conditions arise in the chisel holder 30 that attempt to move the plug-in end 44 of the chisel holder 30 out of the plug-in receptacle 18 in the direction of the plug-in end's longitudinal axis 44.2. Since, as described above, the front shank contact surface 45, together with the front cutting surfaces 41.1, 41.2, each encloses the undercut angle γ, which is selected in the range between at least 103° and at most 114°, an undercut acting in the direction of the plug-in end's longitudinal axis 44.2 is created, thus generating a positive-locking connection in the direction of the plug-in end's longitudinal axis 44.2. This positive-locking connection therefore prevents the plug-in end 44 from being pulled out of the plug-in receptacle 18 in the event of overload.

[0146] Fig. Figure 2 illustrates that with the chisel holder 30 mounted, an ejector tool can be guided through the ejector receptacle 36 towards the chisel holder 32. Since the ejector receptacle 36 widens radially towards the central longitudinal axis M of the chisel holder 32, ample space is provided for the ejector tool. This facilitates the removal of the chisel.

[0147] During machining, the machining forces are transferred from the tool holder 30 to the lower part 10. The force is transferred from the front cutting surfaces 41.1, 41.2 and the rear cutting surfaces 43.1, 43.2 of the tool holder 30 to the front support surfaces 15.1, 15.2 and the rear support surfaces 16.1, 16.2 of the lower part 10.

[0148] As the tool's usage time increases, the front cutting surfaces 41.1, 41.2 and the rear cutting surfaces 43.1, 43.2 and / or the front support surfaces 15.1, 15.2 and the rear support surfaces 16.1 and 16.2 may wear down. This causes the tool holder 30 to shift relative to the lower part 10. The use of the inclined surfaces 42.1, which face the lower part 10 in the area of ​​the recesses 17, provides a generous adjustment space (see Fig. 3) created, which compensates for this wear. Thus, the chisel holder 30 can continue to be reliably and as intended supported on the front and rear support surfaces 15.1, 15.2, 16.1, 16.2 of the lower part 10. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] EP 2 729 666 A2 [0017, 0018]

Claims

[1] A chisel holder (30) for a soil cultivation machine, in particular for a road milling machine, a stabilizer, a recycler, or a surface miner, comprising a support body (35) which has a chisel receptacle (32) or carries a cutting tip in the area of ​​a working side, wherein the support body (35) indirectly or directly carries a plug socket (44) on a plug socket side, wherein the plug socket (44) has a plug socket longitudinal axis (44.2), wherein the plug socket longitudinal axis (44.2) lies in a central longitudinal plane (ME) of the chisel holder (30), wherein the support body (35) has two front planar cutting surfaces (41.1, 41.2) forming a pair of cutting surfaces, which are at an angle to each other such that they enclose a transverse support angle (α) and which are arranged at least partially in front of the plug socket (44), wherein the front cutting surfaces (41.1, 41.2) extend laterally from the plug-in end (44) towards the rear of the chisel holder (30) beyond the plug-in end longitudinal axis (44.2) of the plug-in end (44), and wherein the support body (35) has at least one rear cutting surface (43.1, 43.2) which forms an obtuse longitudinal support angle (β) with the front cutting surfaces (41.1, 41.2) and which is arranged at least partially behind the plug-in end (44), . characterized by , that the front cutting surfaces (41.1, 41.2) transition laterally to the plug-in base (44) via at least one inclined surface (42.1) directly or indirectly into the rear cutting surface (43.1, 43.2) or into one of the rear cutting surfaces (43.1, 43.2). [2] Chisel holder (30) according to claim 1, characterized by, that the inclined surfaces (42.1) each extend in the area between two transverse edges, wherein the front transverse edge facing the front of the chisel holder (30) forms a transition between the front cutting surface (41.1, 41.2) and the inclined surface (42.1) and the rear transverse edge facing the rear of the chisel holder (30) forms a transition between the inclined surface (42.1) and the associated rear cutting surface (43.1, 43.2), that the maximum distance between the two transverse edges, measured parallel to the central longitudinal plane (ME), is less than the extent of the plug-in extension (44) measured parallel to the central longitudinal plane (ME), wherein it is preferably provided that the maximum distance (X) between the two transverse edges, measured parallel to the central longitudinal plane (ME) and perpendicular to the plug-in extension longitudinal axis (44).2) is smaller than 0.7 times, preferably smaller than 0.6 times, the extent of the plug-in extension (44) measured parallel to the central longitudinal plane (ME) and / or that the minimum distance (X) between the two transverse edges, measured parallel to the central longitudinal plane (ME) and perpendicular to the plug-in extension longitudinal axis (44.2), is greater than 0.2 times the extent of the plug-in extension (44), measured in the central longitudinal plane (ME) and perpendicular to the plug-in extension longitudinal axis (44.2). [3] Chisel holder (30) according to claim 2, characterized by , that both transverse edges of the inclined surfaces (42.1) are inclined at an angle (ε) less than 90°, preferably at an angle (ε) less than 70° in the direction from the front of the chisel holder (30) to the rear of the chisel holder (30) and inclined to the central longitudinal plane (ME). [4] Chisel holder (30) according to one of claims 1 to 3, characterized by , that the inclined surfaces (42.1) are designed as a planar surface. [5] Chisel holder (30) according to any one of claims 1 to 4, characterized by , that the inclined surfaces (42.1) form an obtuse angle with both the associated front cutting surface (41.1, 41.2) and the rear cutting surface (43.1, 43.2). [6] Chisel holder (30) according to any one of claims 1 to 5, characterized by , that on both sides of the plug-in attachment (44) an inclined surface (42.1) is provided which directly or indirectly transitions the associated front cutting surface (41.1, 41.2) into a rear cutting surface (43.1, 43.2), wherein the two rear cutting surfaces (43.2, 43.2) lie in a common plane or are arranged at an angle to each other. [7] Chisel holder (30) according to any one of claims 1 to 6, characterized by, that the inclined surfaces (42.1) in view along the longitudinal axis of the insertion point (44.2) are set in a V-shape towards each other on the underside of the chisel holder (30), and diverge in the direction from the front of the chisel holder (30) towards the back of the chisel holder (30) and / or diverge from the underside of the chisel holder (30) towards the top of the chisel holder (30). [8] Chisel holder (30) according to any one of claims 1 to 7, characterized by, that the plug-in end (44) at its end facing the support body (35) transitions directly or indirectly into the support body (35) by means of a shaft widening (44.1), that the shaft widening (44.1) extends laterally to both sides of the plug-in end (44) with widening sides and widens the cross-section of the plug-in end (44) in these areas towards the support body (35), and that the extension of the widening sides in the direction of the plug-in end longitudinal axis (44.2) is at least in one area at least 5%, preferably at least 10%, particularly preferably at least 14% of the length of the plug-in end (44) in this direction. [9] Chisel holder (30) according to claim 8, characterized by, that the widening sides of the shaft widening (44.1) extend over the entire depth of the plug insertion (44) running parallel to the central longitudinal plane (ME) and perpendicular to the plug insertion longitudinal axis, or extend over at least 50% of the depth of the plug insertion (44). [10] Chisel holder (30) according to one of claims 8 or 9, characterized by , that the widening sides of the shaft widening (44.1) extend convexly and arcuately to the front end area of ​​the plug socket (44). [11] Chisel holder (30) according to one of claims 8 to 10, characterized by, that the shaft widening (44.1) forms a rear shaft assembly (48) on the rear side, wherein the rear shaft assembly (48) has two side contact surfaces (48.1) arranged apart from each other, which are connected to each other indirectly or directly by means of an overload contact surface (48.2), wherein it is preferably provided that the side contact surfaces (48.1) are designed as flat surfaces and are arranged in a V-shape relative to each other, in particular at an angle to each other, wherein it is preferably provided that the angle between the two side contact surfaces (48.1) is selected in the range between 45° and 100°, preferably between 55° and 90°, and particularly preferably between 66° and 76°. [12] Chisel holder (30) according to any one of the preceding claims, characterized by, that the extension intersects at least one of the transverse edges bounding the inclined surfaces (42.1), preferably both transverse edges, the associated side contact surface (48.1) of one side of the chisel holder (30). [13] Tool system comprising a chisel holder (30) according to one of claims 1 to 12 and a lower part (10) wherein the chisel holder (30) is attached with its plug-in end (44) in a plug-in receptacle (18) of the lower part (10), and wherein the two inclined surfaces (42.1) of the chisel holder (30) are spaced apart from the lower part (10) in the area of ​​recesses (17) of the lower part (10), each forming a recess space opposite the lower part (10). [14] Tool combination according to claim 13, characterized by , that the recesses (17) are formed as trough-shaped depressions. [15] Tool combination according to claim 13 or 14, characterized by, that the front and / or the rear removal surfaces (41.1, 41.2; 43.1, 43.2) extend into the area of ​​the recesses (17), preferably being provided that at least one of the transverse edges that define the inclined surfaces (42.1) is arranged spaced apart from the lower part (10) in the area of ​​the respective associated recess (17).

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