Indexing method for cutting tools and cutting inserts

Abstract

The cutting tool (1) includes a tool carrier (2) on which at least one seat (3) for receiving an exchangeable, indexable cutting insert (4) is formed, and a clamping screw (5) for supporting the cutting insert (4) in the seat (3). The clamping screw has a head (50) for support on the cutting insert (4) and a shank (51) having at least a partial external thread (52). The seat (3) has a support surface (30) for supporting a bottom surface (40) of the cutting insert (4) and at least one lateral support surface (31) for supporting a lateral surface (41) of the cutting insert (4). A through hole (6) is formed in the support surface (30), through which the shank (51) of the clamping screw (5) extends. The clamping element 7 is arranged behind the support surface 30 of the seat 3 of the tool carrier 2 and is provided with an internal thread 72 which cooperates with the external thread 52 of the clamping screw 5. The clamping screw 5 and the clamping element 7 can be displaced together in the displacement direction V.

Description

[Technical field]

[0001] The present invention relates to a cutting tool and a method for indexing a cutting insert. [Background technology]

[0002] In particular, in the machining of metallic materials, cutting tools are often used in which the cutting edges that engage the workpiece are formed on replaceable cutting inserts made of a hard, wear-resistant material, in particular hard metals (hard alloys), cermets or cutting ceramics, and are removably mounted on a tool carrier made of a tougher material, such as tool steel. The cutting inserts are often designed as so-called indexable cutting inserts, which have several individually usable cutting edges, one after the other, when the previous one wears out. In this case, the cutting edges are usually arranged such that the cutting insert has a certain degree of symmetry, and the indexing or switching to bring the next cutting edge into the working position is performed by rotating the cutting insert through a certain angular range around the axis of symmetry of the cutting insert.

[0003] DE 10 200 03 133 A1 describes a cutting insert for turning with a polygonal basic shape, in which a total of six cutting edges are formed in the transition from the top to the side surface, which can be used in sequence, so that the indexing or switching to the next cutting edge is performed by rotating 60° (=360° / 6) about the axis of symmetry. The described cutting insert is designed to be accommodated in the seat of a peeling cassette as a tool carrier, and the mounting is performed via a clamping screw, the head of which is supported on the cutting insert and the shank of which is provided with an external thread and is adapted to cooperate with the internal thread of the threaded hole in the seat of the peeling cassette. To index the cutting insert, the clamping screw is completely removed, the cutting insert is rotated 60° in the seat, and then the shank of the clamping screw is reinserted through the through-hole of the cutting insert and its external thread is screwed into the internal thread of the threaded hole. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Patent Application Publication No. 2017 / 143368 Summary of the Invention [Problem to be solved by the invention]

[0005] It is an object of the present invention to provide an improved cutting tool and an improved method for indexing cutting inserts, which in particular allows for simpler and more time-saving indexing. [Means for solving the problem]

[0006] This problem is solved by a cutting tool according to claim 1. Advantageous embodiments are set forth in the dependent claims.

[0007] The cutting tool has a tool carrier in which at least one seat for receiving an exchangeable, indexable cutting insert is formed, and a clamping screw for fixing the cutting insert to the seat, the clamping screw having a head for supporting on the cutting insert and a shank with an external thread at least in a partial area. The seat has a support surface for supporting the lower side of the cutting insert and at least one lateral support surface for supporting a lateral side of the cutting insert. A through hole is formed in the support surface, through which the shank of the clamping screw extends. A clamping member is arranged on the tool carrier behind the support surface of the seat, which is formed with an internal thread that cooperates with the external thread of the clamping screw. The clamping screw and the clamping member can be displaced together in the displacement direction.

[0008] A clamping member is provided which cooperates with the fastening screw, such that the fastening screw and the clamping member can be displaced together in the displacement direction, so that the side of the cutting insert can be removed from the lateral support surface by slightly loosening the screw connection and displacing the fastening screw and the clamping member together with the cutting insert held by the fastening screw, so that the cutting insert can be indexed by rotation about the thread axis of the fastening screw without completely removing the fastening screw. Indexing can thus be performed very simply and quickly, and the cutting insert is secured against falling during indexing. Easy loosening of the screw connection requires only a relatively small rotation of the fastening screw about its thread axis. The lower surface of the cutting insert can be supported, for example, directly on the mounting surface or indirectly, for example, via a support plate arranged between the lower surface of the cutting insert and the mounting surface. The lateral support surface preferably extends perpendicular to the mounting surface.

[0009] According to one embodiment, the tool carrier also has a stop which limits the simultaneous displacement of the clamping screw and the clamping member, which allows particularly easy handling and reduces the displacement to the extent required for indexing. The stop can be formed, for example, by a side surface of a through hole which limits the movement of the clamping screw or by a boundary wall of a recess which receives the clamping member and limits its movement.

[0010] According to one embodiment, the displacement direction has a directional component perpendicular to the lateral support surface, in which case the cutting insert can be moved sufficiently away from the lateral support surface with only a small displacement to allow indexing, and the displacement direction can additionally have a directional component parallel to the lateral support surface.

[0011] According to one embodiment, the seat has at least one further lateral support surface for supporting the cutting insert on another side. In this case, the cutting insert can also be held in the seat with a form-locking element in a particularly secure manner, so that unintentional loosening of the screw connection between the clamping screw and the clamping element due to forces occurring during cutting is counteracted. This lateral support surface preferably extends in a plane different from the plane in which the lateral support surface extends. This further lateral support surface preferably extends perpendicularly to the rest surface.

[0012] According to one embodiment, the displacement direction has a directional component perpendicular to the further lateral support surface, in which case the cutting insert can be moved sufficiently away from the further lateral support surface with only a small displacement, so that indexing is possible.

[0013] If the lateral support surface and the further lateral support surface have a seat side interior angle α<90°, as seen in a direction perpendicular to the support surface, the cutting insert is held in the seat with a form-fitting member in a particularly reliable manner.

[0014] According to one embodiment, the through-hole is formed as an elongated hole having an elongated cross-sectional shape, the longitudinal axis of which runs in the displacement direction. In this case, the reduction in the effective mounting surface due to the through-hole is kept small. Furthermore, the displacement direction can be determined in this case by the shape of the through-hole. The cross-sectional shape of the elongated hole can be various, for example, approximately rectangular, a rectangular basic shape with curved short sides, etc.

[0015] According to one embodiment, the clamping element is accommodated in a rear recess of the tool carrier. In this case, the direction and extent of the displacement can be predetermined in a simple manner by the shape of the recess. Furthermore, the prevention of rotation of the clamping element when the clamping screw is actuated can be achieved in a simple manner by the shape of the recess. Preferably, the clamping element is held in the recess in such a way that it is fixed against rotation and displaceable in the displacement direction.

[0016] According to one embodiment, the cutting tool is a peeling cassette, which in this case preferably has at least two seats for accommodating exchangeable cutting inserts.

[0017] According to one embodiment, the cutting tool has an exchangeable, indexable cutting insert disposed in a seat.

[0018] If the cutting insert has a through-bore with a smaller cross section than the head of the clamping screw, the cutting insert is held particularly reliably against falling off during indexing.

[0019] The above object is also achieved by a method for indexing cutting inserts according to claim 14. Advantageous embodiments are presented in the dependent claims.

[0020] This is a method for indexing a cutting insert into a seat of a cutting tool, the cutting tool having a clamping screw for fixing the cutting insert into the seat, the clamping screw having a head for supporting the cutting insert and a shank having an external thread at least in a partial area, the seat having a support surface for supporting the lower surface of the cutting insert and at least one lateral support surface for supporting a side surface of the cutting insert, the shank of the clamping screw passing through a through hole of the support surface, the external thread cooperating with an internal thread of a clamping member displaceably arranged on the rear surface of the support surface. The method comprises the following steps: loosening the threaded connection between the male thread of the clamping screw and the female thread of the clamping member without completely loosening the clamping screw from the clamping member; displacing the replaceable and indexable cutting insert held by the clamping screw, the clamping member and the clamping screw together in a displacement direction so that the side surface of the cutting insert does not abut against the side support surface; indexing the cutting insert by rotating the cutting insert through a predetermined angle range around the thread axis of the clamping screw; displacing the clamping screw, the clamping member and the cutting insert together towards the lateral support surface, thereby fixing the cutting insert laterally against the lateral support surface; Tightening the threaded connection between the male thread of the clamping screw and the female thread of the clamping member so that the cutting insert is fixed in the seat.

[0021] By loosening the screw connection, displacing the clamping screw, the clamping member and the cutting insert together, indexing and displacing them together again until the lateral surface of the cutting insert abuts against the lateral support surface, the cutting insert can be indexed in a particularly simple and rapid manner in order to bring the next cutting edge into the working position after the cutting edge has been worn, the cutting insert being secured against falling off even during the indexing.

[0022] According to one embodiment, the simultaneous displacement takes place in a displacement direction which has a directional component perpendicular to the lateral support surfaces, in which case only small displacement intervals are necessary to allow indexing.

[0023] According to one embodiment, the clamping member is held against rotation on the cutting tool. This can be achieved, for example, by form-fittingly receiving the clamping member in a recess in the cutting tool. The anti-twist structure allows for particularly simple and convenient indexing.

[0024] According to one embodiment, the clamping screw and the clamping member are guided in the displacement direction in the cutting tool when they are displaced together via the through-hole and / or the recess for the clamping member. This can be achieved, for example, by forming the through-hole as an elongated hole or by forming the recess in such a way that the clamping member is guided therein like a rail. In this case, the indexing can be performed in a particularly convenient manner. [Brief description of the drawings]

[0025] Further advantages and suitability of the invention will become apparent from the following description of an embodiment with reference to the attached drawings, in which: FIG.

[0026] [Figure 1] 1 is a schematic perspective view of a cutting tool according to a first embodiment. [Diagram 2] 5A-5C are schematic cross-sectional views of a cutting tool in a seat region for an exchangeable, indexable cutting insert with a tightening screw, the cross-sectional view corresponding to the section along the line II-II in the subsequent FIG. 5A-5C. [Diagram 3] FIG. 4 is a schematic partial plan view of the seat area without the cutting insert. [Figure 4] Schematic view of the tool carrier area behind the seat. [Diagram 5] Schematic view of the tool carrier area at the rear of the seat with an exchangeable, indexable cutting insert accommodated in the seat in the clamped position. [Figure 6] FIG. 6 is a schematic view corresponding to FIG. 5 with the replaceable, indexable cutting insert in an index position. [Figure 7] FIG. 13 is a schematic partial plan view of a seat housing an exchangeable, indexable cutting insert in a clamped position; [Figure 8] 8 is a partial view corresponding to FIG. 7 of the cutting insert in the index position. [Figure 9] FIG. 4 is a schematic perspective view of a cutting tool according to a second embodiment with an exchangeable, indexable cutting insert held in a clamped position; [Figure 10] FIG. 6 is a schematic perspective view of a cutting tool according to a second embodiment, the cutting insert being in an index position; [Figure 11] FIG. 4 is a schematic cross-sectional view of the seat area of ​​the variant in the clamped position. [Figure 12] FIG. 4 is a schematic cross-sectional view of the seat area of ​​the modified embodiment in an index position; [Figure 13] FIG. 5 is a schematic view of the tool carrier area of ​​the seat back in a further variant; [Figure 14] Schematic view of the tool carrier area of ​​the seat back in a further variant in the clamping position. [Figure 15] FIG. 15 is a schematic diagram of the variant of FIG. 14 in an index position.

[0027] First embodiment A first embodiment of a cutting tool will be described below with reference to FIGS.

[0028] In a first embodiment, the cutting tool 1 is formed as a turning cassette for turning. In turning, a surface layer is removed from an approximately cylindrical workpiece by cutting, so that the diameter of the workpiece becomes smaller. In this case, a relative movement is performed between the workpiece and the cutting tool 1 around the longitudinal axis of the workpiece. For example, the workpiece can be rotated around its longitudinal axis and the cutting tool 1 is moved radially with a given depth of cut and axially along the longitudinal direction of the workpiece with a given feed, or the workpiece is moved along its longitudinal axis with a given feed relative to the cutting tool 1 without rotating around its longitudinal axis and the cutting tool 1 is moved radially on a circular path around the longitudinal axis of the workpiece with a given depth of cut. During turning, a number of such cutting tools 1 can also be used simultaneously, distributed around the workpiece.

[0029] The cutting tool 1 comprises a tool carrier 2, in which in a first embodiment a total of two seats 3, 3' are formed for accommodating exchangeable and indexable cutting inserts 4, 4'. The tool carrier 2 can for example be made of steel.

[0030] In the example specifically shown in Figs. 1 to 8, the first cutting insert 4 of the exchangeable and indexable cutting inserts 4, 4' is designed for rough machining of the workpiece, and the second cutting insert 4' is designed for finishing the workpiece surface produced by the first cutting insert 4. In use, the relative movement between the cutting tool 1 and the workpiece is performed in such a way that the second cutting insert 4' follows the first cutting insert 4 in the feed direction. In this embodiment, the first cutting insert 4 preferably has an approximately hexagonal basic shape. However, other, in particular polygonal, shapes are also possible. The second cutting insert 4' has an approximately triangular basic shape. However, other basic shapes are also possible for the second cutting insert 4'.

[0031] In the following, only the area of ​​the first seat portion 3 and the cutting insert 4 arranged thereon will be described in more detail with reference to Figs. 2 to 8.

[0032] As can be seen in particular in Figures 1, 2, 7 and 8, the cutting insert 4 has a top surface 43, a bottom surface 40 and a number of side surfaces extending between the top surface 43 and the bottom surface 40, of which a side surface 41 and another side surface 42 are indicated by symbols in the figures as an example. At least at the transition from the top surface 43 to the side surface, a cutting edge 44 is formed, which has a number of cutting edge portions 45 that can be successively moved into an active cutting position by indexing or switching, one of which is illustrated in Figure 7. In the example of an approximately hexagonal basic shape of the cutting insert 4 specifically shown in the figures, a total of six cutting edge portions 45 are formed at the transition from the top surface 43 to the side surface, which can be used successively. However, it is also possible to provide more than six or less than six cutting edge portions 45 that can be used successively, which is particularly preferred, for example, when the basic form of the cutting insert 4 is different. The cutting insert has a through hole 46 extending from the top surface 43 to the bottom surface 40.

[0033] The cutting insert 4 can be designed, for example, as a one-sided cutting insert in which the cutting edge 44 is formed only at the transition from the top surface 43 to the side surface, but can also be designed, for example, as a double-sided cutting insert in which a further cutting edge is also formed at the transition from the bottom surface 40 to the side surface.

[0034] The seat 3 of the tool carrier 2 is explained in more detail below with reference to FIG.

[0035] As can be seen from Fig. 3, the seat 3 has a support surface 30 configured to support the bottom surface 40 of the cutting insert 4. The support surface 30 can be configured to extend at least mainly in one plane and to be in direct contact with the bottom surface 40 for directly supporting it. However, it is also possible, for example, to arrange an underlay between the bottom surface 40 of the cutting insert 4 and the support surface 30, via which the bottom surface 40 is indirectly supported by the support surface 30.

[0036] As can also be seen in FIG. 3, the seat 3 has a lateral support surface 31 for supporting a side surface 41 of the cutting insert 4. In this case, the lateral support surface 31 preferably extends in a plane perpendicular to the mounting surface 30 of the seat 3. The seat 3 also has another lateral support surface 32 for supporting another side surface 42 of the cutting insert 4. This lateral support surface 32 preferably also extends in a plane perpendicular to the mounting surface 30 of the seat 3. Alternatively, for example, it is also possible for the lateral support surface 31 to extend at an angle other than 90° to the mounting surface 30, for example when the side surface of the cutting insert is not perpendicular to the bottom surface. In this case, the lateral support surface 32 also preferably extends at the same angle other than 90° to the mounting surface 30.

[0037] As can be seen from Fig. 3, the lateral support surface 31 and the further lateral support surface 32 enclose a seat-side interior angle of less than or equal to 90°, as viewed perpendicular to the resting surface 30. In the illustrated specific embodiment in which the cutting insert 4 has an approximately hexagonal basic shape, the interior angle can be, for example, about 60°. If the lateral support surface 31 and the further lateral support surface 32 do not extend perpendicular to the resting surface 30, the interior angle α will be measured in a plane parallel to the resting surface 30 between the lateral support surface 31 and the further lateral support surface 32.

[0038] As can also be seen in particular in Figure 3, a through hole 6 is formed in the bearing surface 30 of the seat 3, which runs from the bearing surface 30 to the rear surface of the tool carrier 2 opposite the bearing surface 30. In the embodiment shown, the through hole 6 is formed as a hole having an elongated cross-sectional shape with a longitudinal axis L in a plane parallel to the bearing surface 30.

[0039] Also provided is a clamping screw 5 for securely fixing the cutting insert 4 in the seat 3. The clamping screw 5 extends along the thread axis Z and, as can be seen in particular in FIG. 2, has a head 50 for support on the cutting insert 4 and a shank 51 extending from the head 50 along the thread axis Z. The shank 51 is provided with an external thread 52 at least at the end opposite the head 50. The head 50 of the clamping screw 5 has a larger cross section in a direction perpendicular to the longitudinal axis of the clamping screw 5 than the through hole 46 of the cutting insert 4.

[0040] In particular, a recess 8 is formed on the rear side of the support surface 30 of the tool carrier 2, as can be seen in Fig. 4. In this embodiment, the recess 8 is formed as an elongated recess, the longitudinal axis Y of which runs parallel to the longitudinal axis L of the through-bore 6.

[0041] In the exemplary embodiment shown, the recess 8 is formed as a recess which is open, for example, only on the side facing away from the rest surface 30 and is otherwise enclosed. The recess 8 can, for example, in particular have an approximately rectangular cross-sectional shape. However, according to a variant, the recess can also be closed on the side facing away from the rest surface 30, for example by a cover.

[0042] As can be seen in particular in Figures 2, 5 and 6, a clamping element 7 is arranged in the recess 8. The clamping element 7 is provided with an internal thread 72 which cooperates with the external thread 52 of the clamping screw 5. The clamping screw 5 is passed with its shank 51 through the through hole 46 of the cutting insert 4 and through the through hole 6 of the tool carrier 2, the external thread 52 of the clamping screw 5 being screwed into the internal thread 72 of the clamping element 7. The head 50 of the clamping screw 5 is supported by the cutting insert 4. Due to the fact that the cross section of the head 50 is larger than the cross section of the through hole 46 of the cutting insert 4, the cutting insert 4 is fixed against falling off even if the clamping screw 5 is not fully tightened. For this purpose, the through hole 46 of the cutting insert 4 can be provided in a region close to the upper surface 43 of the cutting insert 4, in particular with a shape adapted to the underside of the head 50.

[0043] In this case, the clamping member 7 is adapted to the shape of the recess 8 so that it can be displaced along the longitudinal axis Y of the recess 8, but in the direction perpendicular to the longitudinal axis Y and perpendicular to the screw axis Z, its width corresponds to the width of the recess 8 and it is held in the recess 8 so that rotation about the screw axis Z is prevented. In the direction of the longitudinal axis Y of the recess 8, the clamping member 7 is shorter than the recess 8 in order to be able to be displaced in this direction.

[0044] When the clamping screw 5 is not tightened, the above-described configuration allows the clamping screw 5 and the clamping member 7 to be displaced together in a displacement direction V running parallel to the longitudinal axis Y of the recess 8. Note that, due to the configuration of the through hole 6 as an elongated hole as described above, the displacement direction V is also parallel to the longitudinal axis L of the elongated cross-sectional shape of the through hole 6.

[0045] In order to allow displacement in the displacement direction V, the through hole 6 must be at least larger around the displacement path than the diameter of the shank 51 of the clamping screw 5, at least in the displacement direction V.

[0046] In the first embodiment, the possible displacement of the clamping screw 5 and the clamping member 7 in the displacement direction V is limited. In the example shown, one side wall of the recess 8 forms a stop 81 which limits the displacement of the clamping member 7. Alternatively or additionally, the displacement can also be limited via a stop 61 formed by the side wall of the through hole 6 relative to the shank 51 of the clamping screw 5.

[0047] In this embodiment, the displacement direction V has a directional component perpendicular to the lateral support surface 31 and a directional component perpendicular to the further lateral support surface 32. The displacement direction V therefore runs neither parallel to the lateral support surface 31 nor parallel to the further lateral support surface 31. In the first embodiment, the displacement direction V runs in a cross section perpendicular to the thread axis Z, in particular along the bisector between the lateral support surface 31 and the further lateral support surface 32.

[0048] In the following, the method of indexing the cutting insert 4 in the seat portion 3 of the cutting tool 1 will be described in more detail.

[0049] In the clamped position, as shown for example in Figures 1, 2, 5 and 7, the cutting insert 4 is clamped by the clamping screw 5 in the direction of the bearing surface 30 and rests with a lateral side 41 against the lateral support surface 31 and with a further lateral side 42 against the further lateral support surface 32. In this case, the cutting insert 4 is held partly by frictional lock via the clamping screw 5 and partly by positive lock against rotation about the screw axis Z via the lateral support surface 31 on the seat 3 and the additional further lateral support surface 32.

[0050] To index the cutting insert 4, i.e. to bring the rear cutting edge portion 45 of the cutting edge 44 into the working position, the clamping screw 5 only needs to be loosened slightly. This can be done, for example, by engaging a screwdriver into a corresponding point (not shown in detail) on the head 50 of the clamping screw 5. The screwed connection between the external thread 52 of the clamping screw 5 and the internal thread 72 of the clamping member 7 is not completely released, but only the clamping torque is loosened. This can be achieved, for example, by simply turning the clamping screw 5, depending on the specific design of the thread. The anti-twist arrangement of the clamping member 7 in the recess 8 prevents the clamping member 7 from rotating together about the screw axis Z.

[0051] By loosening the threaded connection, the clamping between the cutting insert 4, the clamping member 7 and the area of ​​the tool carrier 2 lying between them is released. In this state, the clamping screw 5, the clamping member 7 and the cutting insert 4 can be moved together in a displacement direction V into the index position shown diagrammatically in Figs. 6 and 8. The cutting insert 4 is secured against falling out via the head 50 of the clamping screw 5. During this displacement, the shank 51 of the clamping screw 5 moves in the through hole 6 in the displacement direction V, and the clamping member 7 moves in the recess 8 in the displacement direction V.

[0052] Due to the mutually matched shapes of the clamping member 7 and the recess 8, the clamping member 7 is guided in the recess 8 like a rail. By forming the through hole 6 as an elongated hole, the shank 51 of the clamping screw 5 is also guided in the through hole 6.

[0053] The movement in the displacement direction V can take place until it is limited by the stops 61 and / or 81. During this movement, the side surface 41 of the cutting insert 4 moves away from the lateral support surface 31 and the other side surface 42 of the cutting insert 4 moves away from the other lateral support surface 32, so that the positive form-locking locking of the cutting insert 4 against rotation about the thread axis Z is released.

[0054] In the indexing position, the cutting insert 4 can be rotated about the thread axis Z in order to index it, i.e. to bring the subsequent cutting edge 45 into the active cutting position. In the illustrated embodiment in which the cutting insert 4 has an approximately hexagonal basic shape and six cutting edges 45 are successively usable, the cutting insert 4 is rotated about the thread axis Z, for example, by 60° (=360° / 6) or an integer multiple of 60°. The angular range required for indexing in this case is generally determined by the multiplicity of rotational symmetry of the cutting insert 4 about the thread axis Z.

[0055] After indexing by rotating the cutting insert 4 through a predefined angular range, the clamping screw 5, the cutting insert 4 and the clamping element 7 are again moved together into the clamping position shown in Figures 5 and 7, in which the (different) lateral surface 41 rests against the lateral support surface 31 and the (different) further lateral surface 42 rests against the further lateral support surface 32. In this position the cutting insert 4 is again form-lockingly fixed against rotation about the screw axis Z.

[0056] By subsequently tightening the threaded connection between the clamping screw 5 and the clamping member 7, the cutting insert 4 is again fixed in the seat 3 in such a way that it can no longer move together with the clamping screw 5 and the clamping member 7. The non-rotatable arrangement of the clamping member 7 in the recess 8 prevents the clamping member from rotating when the clamping screw 5 is tightened.

[0057] Second embodiment A second embodiment of a cutting tool will now be briefly described with reference to Figures 9 and 10. In this case, to avoid repetition, only the differences from the first embodiment described above will be described and the same reference numerals as in the first embodiment will be used.

[0058] The cutting tool 1' according to the second embodiment is a turning turn holder in which the tool carrier 2 has only one seat 3 for accommodating an exchangeable, indexable cutting insert 4. In the second embodiment, the illustrated tool carrier 2 is in particular formed as a so-called monoblock turn holder.

[0059] A further difference from the first embodiment described above is that the cutting insert 4 in the second embodiment is indirectly supported on the support surface of the seat portion 3 via a support plate 9 arranged therebetween.

[0060] Further features of the seat 3 and the mechanism for indexing the cutting insert 4 described above are identical to those of the first embodiment described above and therefore will not be repeated.

[0061] In Fig. 9 the cutting tool 1' according to the second embodiment is shown with the cutting insert 4 held in a clamped position. In Fig. 10 the cutting tool 1' is shown with the cutting insert 4 in an indexed position.

[0062] Variations It should be noted that, although in the above-described embodiment the through-hole 6 is described as being configured as an elongated hole as being particularly advantageous, the through-hole can also have a different cross-sectional shape and the displacement direction can only be determined, for example, by guiding the clamping element 7 into the recess 8. It should be noted, however, that the through-hole 6 must have a sufficient oversize with respect to the shank 51 of the clamping screw 5 to allow a sufficient displacement.

[0063] Although a peeling cassette for turning and a monoblock holder for turning have been described as examples of cutting tools, the cutting tools can have different configurations. For example, the application is not necessarily limited to turning, but cutting tools for other cutting applications are also conceivable. However, the described mechanism for indexing the cutting insert is particularly suitable for cutting tools for turning.

[0064] A variant of the cutting tool configuration in the seat area is briefly described below with reference to figures 11 and 12. This variant can be used in combination with the above-mentioned embodiment and variants. The variant shown in figures 11 and 12 differs from the previously described embodiment in that i) the cutting insert 4 is formed as a double-sided cutting insert, ii) the recess 8' and the clamping member 7' are formed with form-locking elements also for holding the cutting insert 4 in the clamped position, and iii) the recess 8' is also closed on the rear side by a cover 10. It should be noted, however, that these differences i), ii) and iii) can also be used individually or in any combination.

[0065] The cover 10 closes the underside of the recess 8' to prevent dirt from getting in. The cover 10 also prevents the clamping member 7' from falling off or being lost when the clamping screw 5 is completely removed.

[0066] As can be seen from figures 11 and 12, the recess 8' has an additional overhanging recess 83 designed to cooperate with the nose-like projection 73 of the clamping member 7'. The recess 83 and the projection 73 interact according to the principle of inclined surfaces, such that when the clamping screw 5 is tightened, the cutting insert 4, the clamping screw 5 and the clamping member 7' are clamped together in the direction of the clamping position, as is evident in figure 11. The interaction between the projection 73 and the recess 83 creates an additional form-lock in the clamping position, so that the fixing in the clamping position does not only take place via surface pressure and friction, as in the above-mentioned embodiment.

[0067] In a further variant, which is shown diagrammatically in Fig. 13, a spring element 11 is additionally provided, which serves to clamp the clamping member and thus indirectly the clamping screw 5 and the cutting insert 4 in the direction of the clamping position. In this way, a particularly favorable indexing is possible. A helical spring is shown diagrammatically as the spring element 11 in Fig. 13, but spring elements of a different design which produce a clamping action in the direction of the clamping position can also be used.

[0068] It should be noted that these further modifications can be used in the two embodiments described above as well as in combination with the variants described above.

[0069] A further variant in which an additional form-locking lock is provided at the clamping point is briefly described below with reference to Figures 14 and 15. The further variant differs from the above-described configuration in that the recess 8 does not have an approximately rectangular basic shape in cross section, but has a clamping part 8a and an index part 8b which is slightly offset from this in relation to the screw axis Z.

[0070] The functionality of this variant will now be briefly described. When the clamping member 7 is in the indexing position shown in FIG. 15, the cutting insert (not shown in FIG. 14 and FIG. 15) can be indexed as described above with respect to the embodiment. Furthermore, the clamping member 7, the clamping screw 5 and the cutting insert 4 can also be displaced in this position in the displacement direction V as described above with respect to the embodiment. If the clamping member 7 together with the clamping screw 5 and the cutting insert 4 is moved along the displacement direction V into the clamping position shown in FIG. 15, the clamping member 7 is first guided through the displacement direction V on the side wall of the recess 8, as previously explained, until the cutting insert 4 abuts against the lateral support surface 31 and another lateral support surface 32. When the clamping screw 5 is tightened, it exerts a rotational torque M on the clamping member 7, as shown diagrammatically by an arrow in FIG. 14. Due to the configuration of the clamping part 8a, which is arranged to rotate slightly relative to the indexing part 8b with respect to the thread axis Z, the clamping member 7 is slightly rotated around the thread axis Z into the clamping position shown in FIG. 14 by the rotational torque exerted by the clamping screw 5. By this rotation, the clamping element 7 is now fixed by the side walls of the clamping part 8a in a form-locking manner against displacement in the displacement direction V. As a result, the cutting insert 4 is positively and positively secured in the clamping position on the clamping screw 5 with a friction-locking fixation.

[0071] This further variant may also be combined in any manner with the above-described embodiments and variants.

Claims

1. A cutting tool (1; 1') comprising a tool carrier (2) formed with at least one seat (3) for receiving an exchangeable and indexable cutting insert (4), a head (50) for supporting said cutting insert (4) on said cutting insert (4) for fixing said cutting insert (4) in said seat (3), a clamping screw (5) having a shank (51) at least partially provided with an external thread (52), and said exchangeable and indexable cutting insert (4) arranged on said seat (3) and provided with a through hole (46) having a smaller cross-sectional area than the head (50) of said clamping screw (5), The seat (3) has a support surface (30) for supporting a bottom surface (40) of the cutting insert (4) and at least one lateral support surface (31) for supporting a side surface (41) of the cutting insert (4), A through hole (6) into which the shaft portion (51) of the fastening screw (5) is fitted is formed in the mounting surface (30), a clamping member (7) is arranged on the back side of the mounting surface (30) of the seat portion (3) of the tool carrier (2), and a female thread (72) is formed in the clamping member (7) to cooperate with the male thread (52) of the fastening screw (5); The clamping screw (5) and the clamping member (7) are displaceable together in a displacement direction (V) for indexing the cutting insert (4), the tool carrier (2) further comprises stops (61, 81) for limiting the common displacement of the clamping screw (5) and the clamping member (7), The displacement direction (V) has a directional component perpendicular to the lateral support surface (31), Cutting tool (1; 1').

2. 2. Cutting tool (1; 1') according to claim 1, wherein the seat (3) has at least one further lateral support surface (32) for supporting a further side surface (42) of the cutting insert (4).

3. 3. Cutting tool (1; 1') according to claim 2, wherein said displacement direction (V) has a directional component perpendicular to said further lateral support surface (32).

4. 4. A cutting tool (1; 1') according to claim 2 or 3, wherein the lateral support surface (31) and the further lateral support surface (32) have an interior angle (α) on the seat side of <90° as seen in a direction perpendicular to the rest surface (30).

5. Cutting tool (1; 1') according to one of the claims 1 to 4, wherein the clamping member (7) is accommodated in a recess (8) on the rear side of the tool carrier (2).

6. 6. Cutting tool (1; 1') according to claim 5, wherein the clamping member (7) is held in the recess (8) non-rotatably but displaceably in the displacement direction (V).

7. A cutting tool (1; 1') according to one of the claims 1 to 6, wherein the cutting tool (1) is a peeling cassette for turning operations.

8. Cutting tool (1; 1') according to claim 7, wherein said cutting tool has at least two seats (3, 3') for accommodating said exchangeable cutting inserts (4, 4').

9. A method for indexing a cutting insert (4) into a seat (3) of a cutting tool (1; 1'), comprising the steps of: the cutting tool (1;1') has a clamping screw (5) for fixing the cutting insert (4) on the seat (3), the clamping screw (5) having a head (50) for supporting on the cutting insert (4) and a shank (51) provided with an external thread (52) in at least a partial area, the seat (3) has a mounting surface (30) for supporting a lower surface of the cutting insert (4) and at least one lateral support surface (31) for supporting a side surface (41) of the cutting insert (4); a shaft portion (51) of the fastening screw (5) passes through a through hole (6) of the mounting surface (30), and the male thread (52) interacts with a female thread (72) in a clamping member (7) displaceably arranged on the opposite side of the mounting surface (30).

1. A method comprising: - loosening the threaded connection between the male thread (52) of the clamping screw (5) and the female thread (72) of the clamping member (7) without completely removing the clamping screw (5) from the clamping member (7); displacing the clamping screw (5), the clamping member (7) and the replaceable and indexable cutting insert (4) held by the clamping screw (5) together along a displacement direction (V) so that the cutting insert (4) does not abut at its side against the lateral support surfaces (31); indexing the cutting insert (4) by rotating the cutting insert through a predetermined angular range about the thread axis (Z) of the clamping screw (5); - displacing the clamping screw (5), the clamping member (7) and the cutting insert (4) together (common displacement) towards the lateral support surface (31) so that the cutting insert (4) abuts against the lateral support surface (31) with a lateral surface (41); - tightening the threaded connection between the male thread (52) of the clamping screw (5) and the female thread (72) of the clamping member (7) so that the cutting insert (4) is tightly clamped in the seat (3); A method for indexing a cutting insert (4) into a seat (3) of a cutting tool (1; 1') having

10. 10. The method according to claim 9, wherein the common displacement is performed in the displacement direction (V) having a directional component perpendicular to the lateral support surfaces (31).

11. 11. The method according to claim 9 or 10, wherein the clamping member (7) is held on the cutting tool (1) such that it is prevented from twisting.

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