Cutting tool with two cutting edges, cutting tool system with cutting tool and method for broaching

Abstract

Cutting tool (2) for cutting longitudinal grooves, for example keyways, with a tool shank (6) extending along a longitudinal central axis (4) for clamping in a tool holder driven in the direction of the longitudinal central axis (4) and a cutting head (8) axially extending the tool shank (6), which has two cutting wedges (10) rotationally symmetrical to each other with respect to the longitudinal central axis (4), wherein the tool shank (6), preferably at its end facing away from the cutting head (10), has a rotation-locking section (24) for positively locking rotation-locking clamping in the tool holder, and the cutting wedges (10) can be aligned with each other by rotation about a predetermined angle of rotation, in particular about 180° or 90° with respect to the longitudinal central axis (4), wherein the rotation-locking section (24) provides anti-rotation protection in a first rotational angular position and a second rotational angular position,which is offset by the predetermined rotation angle to the first rotation angle position, wherein the cutting wedges (10) are formed integrally with the cutting head (8), characterized in that the cutting head (8) is formed integrally with the tool shank (6).

Description

Technical field

[0001] The invention relates to a cutting tool for broaching longitudinal grooves. Furthermore, the invention relates to a cutting tool system comprising such a cutting tool and a method for broaching with such a cutting tool.

[0002] Cutting tools for broaching longitudinal grooves, hereinafter also referred to as broaching tools, are known from the prior art. For example, the applicant markets a broaching tool, such as the "Cutting insert for broaching longitudinal grooves GN106.0211.035.12.06.N", which is made of solid carbide and has exactly one cutting edge formed on a cutting wedge. The width of the cutting edge corresponds to the width of the groove to be produced.

[0003] This cutting tool, however, has the disadvantage that it becomes unusable when the cutting edge wears down. Such a broaching tool can only be reused by resharpening the cutting edge. The broaching tool can then only be used for broaching narrower grooves due to the reduced cutting edge resulting from resharpening. Replacing the cutting wedge is not possible, as the broaching tool is not modular with removable cutting inserts, but rather, due to the high strength requirements, is integrally constructed from solid carbide.

[0004] Publication GB 672,039 A discloses a cutting tool having a double point at both axial ends, wherein the cutting edges of the double point are designed differently in order to perform different machining operations with the same tool. Thus, in the event of wear, the double point cannot be reused to machine the same groove.

[0005] Document WO 2007 / 069862 A1 discloses a tool for machining rectangular grooves into zoom and focus rings of a camera, comprising a first machining part and a second machining part of the same shape and axially symmetrical to it. However, the tool lacks a positive-locking clamping mechanism that defines the rotational positions of the two machining parts. Therefore, the tool must be precisely aligned during repositioning to maintain high manufacturing accuracy and to complete machining of a partially completed workpiece.

[0006] Based on WO 2007 / 069862 A1, the object of the invention is to provide a cutting tool with which work can be carried out for a particularly long time, so that the tool and labor costs for the production of longitudinal grooves can be reduced.

[0007] This problem is solved by a cutting tool according to claim 1. The dependent claims relate to a cutting tool system with a cutting tool according to the invention or to a method for cutting a longitudinal groove using a cutting tool according to the invention. Advantageous embodiments are the subject of the dependent claims.

[0008] The invention relates to a cutting tool for machining longitudinal grooves, for example, keyways. The cutting tool has a tool shank extending along a longitudinal center axis for clamping in a tool holder driven in the direction of the longitudinal center axis, preferably in an alternating back-and-forth motion, and a cutting head extending the tool shank axially. According to the invention, the cutting head has (at least) two cutting wedges that are rotationally symmetrical to each other with respect to the longitudinal center axis. Each cutting wedge has a cutting edge formed by the intersection of a rake face arranged at the end and a clearance face arranged around the circumference.This has the advantage that, when the cutting edge of a first cutting wedge wears, the cutting tool can be unclamped and rotated around its longitudinal center axis until a second cutting wedge is in the same rotational position as the first. The cutting tool can then be clamped in this position, and the cutting edge of the second wedge can be used for further butting of the partially machined longitudinal groove or for butting other longitudinal grooves. Thus, the rotationally symmetrical design of the cutting wedges around the longitudinal center axis ensures that each of the multiple cutting wedges can be brought into a machining position and that all cutting wedges achieve the same manufacturing result in that position, simply by selecting a preferably predetermined rotational position of the cutting tool during clamping.The cutting tool can therefore, after the first cutting wedge has worn away, use the second cutting wedge to cut further identical grooves, thus doubling the tool's service life. The rotation angle of the cutting tool, required to bring the cutting edge of the second wedge into the rotational position of the cutting edge of the first wedge, corresponds to the angular division of the two cutting wedges around their longitudinal center axis.

[0009] Furthermore, the tool shank, preferably at its end furthest from the cutting head, has an anti-rotation section for positive-locking, rotationally secured clamping in the tool holder. This means that the cutting tool can be positively locked in any rotational position via the anti-rotation section. The anti-rotation section can be designed, in particular, to allow only predetermined rotational positions, preferably the predetermined rotational positions in which the cutting edges can be aligned with each other. This means that one cutting edge can be brought into the rotational position of another cutting edge by rotating it by the (predetermined) angle of rotation. This has the advantage that setting the predetermined rotational positions for the cutting edges is particularly easy. As a result, setting the rotational position of the cutting tool is less prone to errors, which can have a positive effect on machining accuracy.It is particularly preferred if the predetermined rotational positions are aligned with the position of the cutting wedges. Preferably, the rotational positions are arranged rotationally symmetrically to each other with respect to the longitudinal center axis. For example, the rotational positions can be aligned with each other and with the arrangement of the cutting edges such that they can only be rotated or clamped in position by the same fixed angle of rotation around the longitudinal center axis as the cutting wedges. The crucial point is that the anti-rotation section is designed such that several rotational positions of the cutting tool can be positively locked in rotation, with the rotational positions corresponding to those in which the cutting wedges are arranged in the machining position.

[0010] Furthermore, the cutting wedges can be aligned relative to each other by rotation through a predetermined angle, in particular 180°, but also, for example, 90°, with respect to the longitudinal center axis. The anti-rotation section provides a locking mechanism in a first rotational position and a second rotational position offset from the first by the predetermined angle. This ensures precise orientation for a two-edged broaching tool (at 180°) or a four-edged broaching tool (at 90°). Additionally, the cutting head is formed integrally with the tool shank.

[0011] In other words, the cutting tool has multiple cutting edges, in particular double or four. However, the cutting tool can also have, for example, six cutting edges. Depending on the number of cutting wedges on the broaching tool, the aforementioned angle of rotation is therefore 180° for a double-edged broaching tool or 90° for a four-edged broaching tool. Consequently, with a four-edged broaching tool, analogous to a two-edged broaching tool, after the first and second cutting wedges have worn down, the third and then the fourth cutting wedge are used, thus quadrupling the tool life. A three-edged or five-edged design is also possible. Preferably, the cutting wedges are evenly distributed around the circumference of the cutting tool.

[0012] According to the invention, the cutting wedges are formed integrally with the cutting head. The cutting wedges are thus formed integrally with a carrier body of the cutting head, in contrast to a modular design where cutting inserts or inserts are detachably held in a carrier body. This means that the cutting wedges cannot be replaced when worn, and the carrier body cannot be reused. Particularly with such an integral design, providing two (or more) equivalently usable cutting wedges offers the advantage that the service life of the cutting tool can be significantly increased, since a second cutting wedge can be used on the same cutting tool after the first one has worn out.

[0013] In a preferred further development, the cutting tool can be made of solid carbide or high-speed steel. This ensures sufficiently high strength and allows for the desired grinding of the cutting wedges. The cutting tool can also be provided with an additional surface coating to advantageously modify the material properties at the surface, and especially in highly stressed areas such as the cutting edge of the wedge.

[0014] According to an advantageous embodiment, the rake faces formed on the cutting wedges can have a positive rake angle. Large positive rake angles between 6° and 25°, preferably between 15° and 20°, have proven particularly suitable for reducing cutting forces. The rake angle is measured between the rake face and a tool reference plane. In the case of a broaching tool, the tool reference plane corresponds to an axial plane perpendicular to the longitudinal center axis of the cutting tool. Consequently, a workpiece-facing end face of the cutting tool is provided with a central notch or recess. In a two-edged design, the recess can, for example, have a triangular shape in longitudinal section.

[0015] In a preferred embodiment, the chip surfaces formed on the cutting wedges can intersect at the level of the longitudinal center axis. This allows the cutting forces to be absorbed particularly well by the cutting tool.

[0016] According to an advantageous further development of the embodiment, the anti-rotation section can be formed by a tongue arranged at a distance transversely to the longitudinal center axis and projecting towards the tool holder to abut a stop on the tool holder side. In other words, the tongue is arranged eccentrically. The eccentric arrangement of the tongue, for example in conjunction with a cylindrical stop arranged transversely, and in particular perpendicularly, to the longitudinal center axis, allows for a positive-locking, anti-rotation clamping of the cutting tool. The tool holder stop can simultaneously serve to define an axial position of the cutting tool.Alternatively, the anti-rotation section of a double-edged broaching tool can have a transverse groove running perpendicular to the longitudinal center axis, while a four-edged broaching tool can have cross-shaped transverse grooves that engage positively with a stop on the tool holder side. The transverse grooves can each have a V-shaped or trapezoidal cross-section, so that the opposing groove flanks are formed by inclined surfaces, similar to the tongue mentioned above.

[0017] According to the advantageous embodiment, the tongue can have a tongue surface that lies at a predetermined angle, preferably parallel, to the cutting edges formed on the cutting wedges and is inclined to the longitudinal center axis. In this way, a mirror-image clamping of the cutting tool can be achieved, i.e., a clamping in a first rotational position and a second rotational position that is offset by 180° to the first rotational position.

[0018] In a preferred embodiment, the tool shank can have a clamping section with a circular cross-section. This has the advantage that conventional clamping mechanisms can be used for tool clamping thanks to the circular clamping section, while at the same time the rotational position can be adjusted via the anti-rotation section.

[0019] In another preferred embodiment, the tool shank can have a clamping section with a polygonal cross-section, for example, a two-sided, (external) square, or (external) hexagonal profile. Due to the non-circular / non-rotationally symmetrical design of the clamping section, it can simultaneously serve as an anti-rotation section. Alternatively, the tool shank, at least in the area of ​​the anti-rotation section, can be formed by a polygonal profile, for example, a two-sided, (external) square, or (external) hexagonal profile. This allows the advantages of a conventional clamping system using, for example, a circular clamping section, to be combined with a polygonal profile as an anti-rotation section.

[0020] The object of the invention is also achieved by a cutting tool system for machining longitudinal grooves, for example keyways, comprising a cutting tool according to the invention and a tool holder holding the cutting tool, wherein the tool holder has a stop that interacts with a rotation-prevention section of the tool shank in such a way that the cutting wedges can be aligned with one another by rotating the cutting tool about the longitudinal central axis. This means that, due to the geometry of the rotation-prevention section in conjunction with the stop of the tool holder, the cutting tool can (only) be clamped in such rotational angular positions / positions that correspond to a rotation about the fixed predetermined angle of rotation.In other words, when clamping (using a double-edged cutting tool as an example), it can be selected whether the cutting tool is clamped in a first rotational position, in which one cutting edge of a first cutting wedge can be engaged in machining, or in a second rotational position, in which one cutting edge of a second cutting wedge can be engaged in machining. Thus, the anti-rotation section simply determines the rotational position of the cutting edges.

[0021] According to a preferred embodiment, the anti-rotation section can be positively locked against the stop to prevent rotation. This makes it particularly easy to implement anti-rotation protection in predetermined positions.

[0022] The object of the invention is also achieved by a method for cutting a longitudinal groove, wherein a cutting tool according to the invention cuts a longitudinal groove in a cutting motion carried out in the direction of the longitudinal center axis, with only one cutting wedge of the cutting tool being in machining engagement with the material. In other words, although the cutting tool is designed with multiple cutting edges, only one cutting edge of several cutting wedges is in machining engagement at any given time, since the other cutting edge or edges do not simultaneously machine the workpiece but serve as a backup cutting wedge. Preferably, the width of the cutting edge of the cutting wedge corresponds to the width of the longitudinal groove to be cut. In this way, the longitudinal groove can be produced with only a few machining steps.

[0023] According to a preferred embodiment of the method, if one of the cutting wedges becomes worn, another cutting wedge can be brought into the rotational position of the first cutting wedge by rotating the cutting tool about its longitudinal center axis. Thus, another cutting wedge can be easily brought into the machining position of the first cutting wedge by simply repositioning it.

[0024] According to a preferred embodiment, the cutting tool according to the invention can create the longitudinal groove in several material removal steps during the preferably reciprocating cutting motion. Preferably, the cutting tool is advanced stepwise in the axial direction, for example in 1 / 10 mm increments. This reduces the mechanical stress on the cutting edge of the wedge and increases its service life. Brief description of the characters Fig. Figure 1 is a side view of a cutting tool according to the invention in a first embodiment, Fig. Figure 2 is a top view of the cutting tool. Fig. 1, Fig. Figure 3 is a front view of the cutting tool. Fig. 1, Fig. Figure 4 is a cross-sectional view of the cutting tool. Fig. 1 along line IV-IV, Fig. Figure 5 is a side view of the cutting tool according to the invention in a second embodiment, Fig. Figure 6 is a top view of the cutting tool. Fig. 5, and Fig. Figure 7 is an enlarged front view of the cutting tool made of Fig. 5.

[0025] The figures are purely schematic and serve solely to illustrate the invention. Identical elements are identified by the same reference numerals. Features of different embodiments can be interchanged as desired. Two embodiments of the present disclosure are described below based on the accompanying figures. First embodiment

[0026] Fig. 1, Fig. 2, Fig. 3 to Fig. Figure 4 shows a first embodiment of a cutting tool 2 according to the invention for broaching longitudinal grooves. Such a cutting tool 2 is also referred to as a broaching tool. For example, the cutting tool 2 is used for broaching keyways. The cutting tool 2 has a tool shank 6 extending along a longitudinal central axis 4. The tool shank 6 serves for clamping in a tool holder (not shown) that can be driven in the direction of the longitudinal central axis 4. The cutting tool 2 also has a cutting head 8 that extends the tool shank 6 axially.

[0027] According to the invention, the cutting head 8 has two cutting wedges 10 that are rotationally symmetrical to each other with respect to the longitudinal center axis 4. The cutting wedges 10 are formed integrally with the cutting head 10 and are integrally formed with the tool shank 6. Each cutting wedge 10 has a rake face 12 and a clearance face 14. The rake face 12 and the clearance face 14 intersect to form a cutting edge 16. The cutting edge 16 is thus formed by the intersection of the rake face 12, which is arranged at the end face, and the clearance face 14, which is arranged around the circumference.

[0028] The rake face 12 has a positive rake angle. The rake angle is formed by the rake face 12 and a tool reference plane, which is an axial plane. The rake angle is between 5 and 25°, preferably between 15 and 20°. The clearance face 14 has a clearance angle. The clearance angle is formed by the clearance face 14 and a cutting plane, which is a radial plane parallel to the longitudinal center axis 4. The clearance angle is between 0 and 10°, preferably between 1 and 5°. A side surface 18 adjoins each of the rake faces 12 and the clearance faces 14. The side surfaces 18 are oriented substantially parallel to each other.

[0029] In the Fig. 1, Fig. 2, Fig. 3 to Fig. In the first embodiment shown in Figure 4, the cutting tool 2 is designed as a double-edged broaching tool. The cutting tool 2 therefore has a first cutting edge 16a and a second cutting edge 16b. The first cutting edge 16a and the second cutting edge 16b are arranged offset from each other by a fixed angle of rotation about the longitudinal center axis 4. The angle of rotation in the first embodiment is 180°. Consequently, the first cutting edge 16a is diametrically opposite the second cutting edge 16b. When clamped, one of the two cutting edges 16a, 16b is in a machining position and the other is in a substitute position. The cutting edges 16a, 16b can be moved to the other position by re-clamping. During re-clamping, the cutting tool 2 is rotated by the angle of rotation about the longitudinal center axis 4.

[0030] The cutting head 8 has a support section 20 which is formed integrally with the cutting wedges 10. The support section 20 has a substantially rectangular cross-section. This is shown in the cross-sectional view of Fig. 4. The cutting wedges 10 are designed such that the cutting edges 16 are parallel to the shorter side of the beam section 20. The shorter side of the cross-section of the beam section 20 is (slightly) smaller than the width of the cutting edges 16. The longer side of the cross-section of the beam section 20 is (slightly) smaller than the distance between the first cutting edge 16a and the second cutting edge 16b.

[0031] The tool shank 6 has a clamping section 22. The clamping section 22 has a circular cross-section (compare Fig. 3 or Fig. 4) Alternatively, the clamping section 22 can also have a square cross-section, for example a polygon such as a two-sided, a square, or a hexagon, although this is not shown. The cutting tool 2 can be clamped in the tool holder via the clamping section 22 using known clamping mechanisms.

[0032] The tool shank 6 has an anti-rotation section 24. The anti-rotation section 24 serves to positively lock and prevent rotation of the cutting tool 2 in the tool holder. The anti-rotation section 24 is designed as a tongue 26 extending axially away from the cutting tool 2. The tongue 26 is arranged eccentrically to the longitudinal center axis 4. This means that the tongue 26 is arranged transversely to the longitudinal center axis 4 at a distance. The tongue 26 projects towards the tool holder. The tongue 26 has a tongue surface 28 that is inclined / angled relative to the longitudinal center axis. The tongue surface 28 is arranged at a predetermined angle, parallel in the illustrated embodiment, to the cutting edges 16. The tongue 26 serves to abut a stop 30 of the tool holder. In the illustrated embodiment, the stop 30 is designed as a cylindrical bolt oriented transversely to the longitudinal center axis 4.The cutting tool 2 can be in a first rotational position, which is in . Fig. The first tool is shown in Figure 1 and is clamped in the tool holder in a second rotational position, which is rotated by the rotation angle, i.e., by 180°, about the longitudinal center axis 4 relative to the first rotational position. Accordingly, in the first rotational position, the first cutting edge 16a is in the machining position, and in the second rotational position, the second cutting edge 16b is in the machining position.

[0033] If the clamping section 22 is designed with a polygonal profile, the polygonal profile can serve as the anti-rotation section 24. The non-rotationally symmetrical design enables a positive-locking, anti-rotation clamping in both the first and second rotational positions. Second embodiment

[0034] Fig. 6 to Fig. Figure 7 shows a second embodiment of the cutting tool 2 for broaching longitudinal grooves. The cutting tool 2 of the second embodiment is designed as a four-edged broaching tool. The design of the second embodiment essentially corresponds to the design of the first embodiment.

[0035] The cutting tool 2 comprises the tool shank 6 extending along the longitudinal center axis 4 and the cutting head 8. The cutting head 8 extends the tool shank 6 axially. According to the invention, the cutting head 8 has four cutting wedges 10 that are rotationally symmetrical to each other with respect to the longitudinal center axis 4. The cutting wedges 10 are formed integrally with the cutting head 10. The cutting head 8 is formed integrally with the tool shank 6. Each cutting wedge 10 has a rake face 12 and a clearance face 14. The four rake faces 12 and the four clearance faces 14 intersect each other and form the cutting edges 16. The rake face 12 has a positive rake angle. The rake angle is between 5 and 25°, preferably between 15 and 20°. The clearance face 14 has a clearance angle. The clearance angle is between 0 and 10°, preferably between 1 and 5°.

[0036] The cutting tool 2 of the second embodiment has a first cutting edge 16a and a second cutting edge 16b opposite the first cutting edge 16a. Additionally, the cutting tool has a third cutting edge 16c and a fourth cutting edge 16d. The third cutting edge 16c and the fourth cutting edge 16d are arranged opposite each other and between the first cutting edge 16a and the second cutting edge 16b. Thus, the four cutting edges 16a, 16b, 16c, 16d are arranged offset from each other by a fixed rotational angle about the longitudinal center axis 4, the rotational angle of the second embodiment being 90°. In the clamped state, one of the four cutting edges 16a, 16b, 16c, 16d is in the machining position, and the other three of the four cutting edges 16a, 16b, 16c, 16d are in the substitute position. The cutting edges 16a, 16b, 16c, 16d can be moved to the other position by repositioning them.During reclamping, the cutting tool 2 is rotated around the longitudinal center axis 4 by the angle of rotation (or a multiple of the angle of rotation).

[0037] The cutting head 8 has the support section 20, which is formed integrally with the cutting wedges 10. The support section 20 of the second embodiment has a substantially cruciform cross-section. This is shown in the side view of Fig. 7 can be seen. The cutting wedges 10 are each arranged parallel to a side surface of the support section 20.

[0038] The tool shank 6 of the second embodiment corresponds to the tool shank of the first embodiment. Accordingly, the tool shank 6 has the clamping section 22 and the anti-rotation section 24. The cutting tool 2 can be clamped in the tool holder in the first rotational position, a third rotational position offset by 90° to the first rotational position, a second rotational position offset by 180° to the first rotational position, and a fourth rotational position offset by 270° to the first rotational position. Accordingly, in the first rotational position, the first cutting edge 16a, in the second rotational position the second cutting edge 16b, in the third rotational position the third cutting edge 16c, and in the fourth rotational position the fourth cutting edge 16d are in the machining position. The other cutting edges 16a, 16b, 16c, and 16d are in the substitute position, in which they cannot be brought into material engagement. Third embodiment

[0039] A third embodiment of the cutting tool according to the invention is described below, although it is not shown in the figures. The design of the third embodiment essentially corresponds to the design of the first and second embodiments and differs only in the design of the anti-rotation section.

[0040] According to the third embodiment, the anti-rotation section of a double-edged broaching tool (compare the first embodiment) is formed by a transverse groove extending across the longitudinal center axis at an end of the tool shank facing the tool holder. Furthermore, according to the third embodiment, the anti-rotation section of a four-edged broaching tool (compare the second embodiment) is formed by cross-shaped transverse grooves at an end of the tool shank facing the tool holder. The transverse groove(s) engage positively with a stop on the tool holder side. The transverse grooves each have, for example, a V-shaped or trapezoidal cross-section, so that the opposing groove flanks are formed by inclined surfaces, similar to the tongue mentioned above. The stop on the tool holder side is therefore a projection extending across the longitudinal center axis and projecting towards the cutting tool.formed as cross-shaped projections that engage in the transverse grooves to secure the cutting tool against rotation.

[0041] The anti-rotation section (or the toolholder-side stop) is thus, like the cutting wedges, rotationally symmetrical about the predetermined angle of rotation, but not rotationally symmetrical about any arbitrary angle about the longitudinal center axis. This defines the rotational positions when clamping the cutting tool.

Claims

[1] Cutting tool (2) for cutting longitudinal grooves, for example keyways, with a tool shank (6) extending along a longitudinal central axis (4) for clamping in a tool holder driven in the direction of the longitudinal central axis (4) and a cutting head (8) axially extending the tool shank (6), which has two cutting wedges (10) rotationally symmetrical to each other with respect to the longitudinal central axis (4), wherein the tool shank (6), preferably at its end away from the cutting head (10), has a rotation-locking section (24) for positively locking rotation-locking clamping in the tool holder, and the cutting wedges (10) can be mapped onto each other by rotation about a predetermined angle of rotation, in particular about 180° or 90° with respect to the longitudinal central axis (4), wherein the rotation-locking section (24) provides anti-rotation protection in a first rotational angular position and a second rotational angular position,which is offset by the predetermined rotation angle to the first rotation angle position, wherein the cutting wedges (10) are formed integrally with the cutting head (8), characterized by , that the cutting head (8) is formed in one piece with the tool shank (6). [2] Cutting tool (2) according to claim 1, characterized by , that the cutting tool (2) is made of solid carbide or high-speed steel. [3] Cutting tool (2) according to claim 1 or 2, characterized by , that the rake surfaces (12) formed on the cutting wedges (10) have a positive rake angle. [4] Cutting tool (2) according to claim 3, characterized by , that the chip surfaces (12) formed on the cutting wedges (10) intersect at the level of the longitudinal center axis. [5] Cutting tool (2) according to any one of claims 1 to 4, characterized by, that the anti-rotation section (24) is formed by a tongue (26) arranged at a distance transverse to the longitudinal center axis (4) and projecting towards the tool holder to abut a stop (30) on the tool holder side. [6] Cutting tool (2) according to claim 5, characterized by that the tongue (26) has a tongue surface (28) which lies at a predetermined angle, preferably parallel, to the cutting edges (16) formed on the cutting wedges (10) and is inclined to the longitudinal central axis (4). [7] Cutting tool (2) according to any one of claims 1 to 6, characterized by , that the tool shank (6) has a clamping section (22) which has the shape of a circle in cross-section. [8] Cutting tool (2) according to any one of claims 1 to 4, characterized by, that the tool shank (6) has a clamping section (22) which has the cross-sectional form of a polygonal profile, or at least the anti-rotation section (24) is formed by a polygonal profile. [9] Cutting tool system for cutting longitudinal grooves, for example keyways, comprising a cutting tool (2) according to one of claims 1 to 8 and a tool holder holding the cutting tool (2) with a stop (30) which interacts with a rotation-prevention section (24) of the tool shank (6) in such a way that the cutting wedges (10) can be aligned with each other by rotating the cutting tool (2) about the longitudinal central axis (4). [10] Cutting tool system according to claim 9, characterized by , that the anti-rotation section (24) is positively locked against the stop (30) and thus prevented from rotating. [11] Method for cutting a longitudinal groove, wherein a cutting tool (2) according to one of claims 1 to 8 cuts a longitudinal groove in a cutting movement carried out in the direction of the longitudinal central axis (4), wherein only a cutting wedge (10) of the cutting tool (2) is in cutting material engagement. [12] Method according to claim 11, characterized by , that if one of the cutting wedges (10) becomes worn, another of the cutting wedges (10) is brought into the rotational position of the first cutting wedge (10) by rotating the cutting tool (2) about the longitudinal central axis (4).

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