CUTTING INSERT FOR RECESS MACHINING, CUTTING INSERT KIT HAVING TWO SUCH CUTTING INSERTS, CUTTING INSERT HOLDER FOR SUCH CUTTING INSERTS, AND METHOD FOR PRODUCING A RECESS

Abstract

The invention relates to a cutting insert holder, having a central axis and at least one first receptacle for fastening a first cutting insert to the cutting insert holder, and having at least one second receptacle for fastening at least one second cutting insert to the cutting insert holder, wherein the first receptacle and the second receptacle are arranged offset from each other in the circumferential direction about the central axis, wherein the first receptacle and the second receptacle are configured and arranged in such a way that a first rake face associated with an active main cutting edge of a first cutting insert arranged in the first receptacle has a first orientation along the circumferential direction, wherein a second rake face associated with an active main cutting edge of a second cutting insert arranged in the second receptacle has a second orientation along the circumferential direction).

Claims

1. Cutting insert holder, having a central axis and at least one first receptacle for fastening a first cutting insert to the cutting insert holder, and having at least one second receptacle for fastening at least one second cutting insert to the cutting insert holder, wherein the first receptacle and the second receptacle are arranged offset from each other in the circumferential direction about the central axis, wherein the first receptacle and the second receptacle are configured and arranged in such a way that a first rake face associated with an active main cutting edge of a first cutting insert arranged in the first receptacle has a first orientation along the circumferential direction, wherein a second rake face associated with an active main cutting edge of a second cutting insert arranged in the second receptacle has a second orientation along the circumferential direction, wherein the first orientation is opposite to the second orientation when the first cutting insert and the second cutting insert are fixed to the cutting insert holder.

2. The cutting insert holder according to claim 1, wherein the cutting insert holder is adapted to a workpiece to be machined in such a way that a first cutting insert arranged on the at least one first receptacle and a second cutting insert arranged on the at least one second receptacle can be fed towards the workpiece separately from one another and, in particular, one after the other in time.

3. Cutting insert for recess machining, with a base body, and a recess protrusion projecting radially from the base body, wherein the recess protrusion comprises a main cutting edge at a work end averted from the base body, and wherein the recess protrusion comprises a deburring cutting edge at least on one side at a transition end facing the base body in the transition area to the base body.

4. The cutting insert according to claim 3, wherein the recess protrusion comprises a deburring cutting edge on both sides at its transition end.

5. The cutting insert according to claim 3, wherein the recess protrusion and the main cutting edge are configured and arranged relative to the base body in such a way that cutting forces are introduced tangentially into the base body during recess machining of a workpiece.

6. The cutting insert according to claim 3, wherein the cutting insert comprises at least one material selected from a group consisting of cemented carbide and cubic crystalline boron nitride, and/or the cutting insert is coated at least in the region of the recess protrusion.

7. The cutting insert according to claim 3, wherein at least one cutting edge stabilization geometry is associated with the main cutting edge, wherein the at least one cutting edge stabilization geometry is preferably selected from a group consisting of a rounding and a chamfer.

8. The cutting insert according to claim 3, wherein the cutting insert (1) is configured as an indexable cutting insert, wherein the cutting insert (1) comprises at least two recess projections (5) arranged offset from each other in a circumferential direction of the base body (3).

9. The cutting insert kit, comprising a first cutting insert according to claim 3, and comprising a second cutting insert, wherein the recess protrusion of the first cutting insert comprises a first working width, and wherein the recess protrusion of the second cutting insert comprises a second working width, and wherein the second working width is larger than the first working width.

10. Method for producing a recesses, in particular a groove, in particular a ring groove (41), in a workpiece, in particular a toothed shaft, having the following steps: Pre-machining the workpiece by cutting a preliminary recess comprising a first width with a first cutting insert, in particular a first cutting insert according to claim 3, wherein a relative rotation of the workpiece to the first cutting insert is effected with a first direction of rotation; Finish machining the workpiece by widening the preliminary recess to a second width, which is greater than the first width, and thus producing the recess, with a second cutting insert, in particular a second cutting insert, wherein a relative rotation of the workpiece to the second cutting insert is effected with a second direction of rotation, wherein the second sense of rotation is opposite to the first sense of rotation, and wherein the resulting recess is deburred during finish machining by means of the second cutting insert.

11. The method according to claim 10, wherein the first relative rotation between the workpiece and a tool comprising the first cutting insert and the second cutting insert, in particular a cutting insert holder, wherein the second relative rotation is effected between the workpiece and the same tool, wherein during pre-machining the first cutting insert is engaged with the workpiece, wherein during finish machining the second cutting insert is engaged with the workpiece.

12. The method according to claim 10, wherein for pre-machining the first cutting insert is fed towards the workpiece, wherein for finish machining the second cutting insert is fed towards the workpiece.

13. The method according to claim 10, wherein a toothed shaft is machined as the workpiece.

14. The method according to claim 10, wherein the recess is introduced into the workpiece in a hardened or quenched and tempered state of the workpiece, wherein the workpiece preferably comprises a hardness of at least 36 HRC to at most 60 HRC.

15. The method according to claim 10, wherein the method is carried out on a vertical lathe, on a horizontal lathe or on a machining center.

Description

[0057] The invention is explained in more detail with reference to the drawing. Thereby show:

[0058] FIG. 1 a first representation of an embodiment of a cutting insert;

[0059] FIG. 2 a second representation of the cutting insert according to FIG. 1;

[0060] FIG. 3 a representation of an embodiment of a cutting insert kit;

[0061] FIG. 4 a first representation of an embodiment of a cutting insert holder;

[0062] FIG. 5 a second representation of the cutting insert holder according to FIG. 4;

[0063] FIG. 6 a third representation of the cutting insert holder according to FIGS. 4 and 5;

[0064] FIG. 7 a representation of a workpiece for machining with the cutting insert according to FIG. 1 and the cutting insert holder according to FIG. 4, and

[0065] FIG. 8 a schematic representation of an embodiment of a method for producing a recess, in particular a groove.

[0066] FIG. 1 shows a first representation of an embodiment of a cutting insert 1. The cutting insert 1 is adapted for recess machining and comprises a base body 3, as well as a recess protrusion 5 projecting radially from the base body 3. In the embodiment shown here, the cutting insert 1 is configured as an indexable cutting insert and comprises two recess protrusions 5 arranged offset from one another in the circumferential direction of the base body 3. The recess projections 5 are preferably configured identically, so that only one of the recess projections 5 will be discussed in more detail below.

[0067] The recess protrusion 5 comprises a main cutting edge 9 at a work end 7 facing away from the base body 3.

[0068] FIG. 2 shows a second representation of the cutting insert 1 according to FIG. 1.

[0069] Identical and functionally identical elements are provided with the same reference signs in all figures, so that reference is made in each case to the preceding description.

[0070] It is clear from the second representation that the recess protrusion 5 comprises a deburring cutting edge 15 at a transition end 11 facing the base body 3 in a transition area 13 to the base body 3 at least on one sideon both sides in the embodiment shown here. The transition end 11 is also referred to as the foot of the recess protrusion 5.

[0071] With the deburring cutting edge 15, it is advantageously possible to remove a burr formed on a workpiece during recess machining efficiently and with little effort.

[0072] In the embodiment shown here, the recess protrusion 5 and the main cutting edge 9 are configured integrally, in particular as a single piece of material, with the base body 3.

[0073] Also shown is a main level 17 of the base body 3, as well as a mounting bore 19 which passes through the base body 3 perpendicular to the main level 17 along an axial direction of the base body 3 and thus at the same time of the cutting insert 1.

[0074] The recess protrusion 5 and the main cutting edge 9 are preferably configured and arranged relative to the base body 3 in such a way that cutting forces are introduced tangentially into the base body 3 during recess machining of a workpiece. In particular, the main cutting edge 9 extends perpendicular to the main level 17, in particular in the axial direction, in particular parallel to the mounting bore 19.

[0075] The cutting insert 1 preferably comprises at least one material selected from a group consisting of cemented carbide and cubic crystalline boron nitride. Alternatively or additionally, the cutting insert 1 is coated at least in the region of the recess protrusion 5.

[0076] In the region of the main cutting edge 9, in particular, a rake face 21 adjoins a flank face 23 of the cutting insert 1. Preferably, the main cutting edge 9 forms a line of intersection between the rake face 21 and the flank face 23.

[0077] Preferably, a cutting edge stabilization geometry 25 is associated with the main cutting edge 9. The cutting edge stabilization geometry 25 is preferably selected from a group consisting of a rounding and a chamfer.

[0078] FIG. 3 shows a representation of an embodiment of a cutting insert kit 27. The cutting insert kit 27 comprises a first cutting insert 1.1 and a second cutting insert 1.2. In this regard, the two cutting inserts 1.1, 1.2 are each preferably configured according to the embodiment previously explained in connection with FIGS. 1 and 2. However, a first recess protrusion 5.1 of the first cutting insert 1.1 has a first working width B1 that is smaller than a second working width B2 of a second recess protrusion 5.2 of the second cutting insert 1.2. In this way, the first cutting insert 1.1 is preferably configured for roughing or pre-machining, while the second cutting insert 1.2 is configured for finishing or finish machining.

[0079] FIG. 4 shows a first representation of an embodiment of a cutting insert holder 29. The cutting insert holder 29 comprises a central axis M and a first receptacle 31 for fastening a first cutting insert 1.1, in particular the first cutting insert 1.1 of the cutting insert kit 27 according to FIG. 3, to the cutting insert holder 29. Furthermore, the cutting insert holder 29 comprises a second receptacle 33 for fastening a second cutting insert 1.2, in particular the second cutting insert 1.2 of the cutting insert kit 27 according to FIG. 3, to the cutting insert holder 29. The central axis M defines an axial direction of the cutting insert holder 29. In particular, the cutting inserts 1.1, 1.2 are held in their respective receptacles 31, 33 in such a way that their respective axial directions, in particular the mounting bores 19, are aligned parallel to the axial direction, i.e. to the central axis M, of the cutting insert holder 29.

[0080] It is also represented that the cutting inserts 1.1, 12 are preferably fastened to the cutting insert holder 29 by means of fastening means 35 configured as fastening screws.

[0081] The first receptacle 31 and the second receptacle 33 are arranged offset from one another in the circumferential direction about the central axis M, in particular diametrically opposite one another.

[0082] The cutting insert holder 29 comprises an interface 37 adapted to connect the cutting insert holder 29 to a machine tool.

[0083] FIG. 5 shows a second representation of the cutting insert holder 29 according to FIG. 4. On the basis of this representation, it is clear that the first receptacle 31 and the second receptacle 33 are configured and arranged in such a way that a first rake face 21.1, assigned to an active main cutting edge 9.1, of the first cutting insert 1.1 arranged in the first receptacle 31 has a first orientation along the circumferential direction, wherein a second rake face 21.2, assigned to an active main cutting edge 9.2, of the second cutting insert 1.2 arranged in the second receptacle 33 has a second orientation along the circumferential direction. Thereby, the first orientation is opposite to the second orientationalong the circumferential direction. The active main cutting edges 9.1, 9.2 are thereby arranged in an engagement position for machining a workpiece. In the embodiment shown here, the recess projections 5.1, 5.2 associated with the active main cutting edges 9.1, 9.2 point radially inwards in the direction of the central axis M, wherein the workpiece is arranged for machining by the cutting inserts 1.1, 1.2 in the region of the central axis M of the cutting insert holder 29.

[0084] Due to the different orientation of the rake faces 21.1, 21.2, a change in the direction of relative rotation between the workpiece and the cutting insert holder 29 is required between machining the workpiece with first the first cutting insert 1.1 and subsequently the second cutting insert 1.2. In this case, in particular, the workpiece can first be pre-machined with the first cutting insert 1.1 and then finish machined with the second cutting insert 1.2, wherein at the same time a burr formed during pre-machining is efficiently removed in the opposite direction to the previous cutting direction.

[0085] In particular, the cutting insert holder 29 is adapted to the workpiece to be machined in such a way that the first cutting insert 1.1 and the second cutting insert 1.2 can be fed towards the workpiece separately from each other and, in particular, one after the other in timein the radial direction.

[0086] FIG. 6 shows a third representation of the cutting insert holder according to FIGS. 4 and 5. Here, on the one hand, the different orientation of the first rake face 21.1 and the second rake face 21.2 along the circumferential direction again becomes clear. On the other hand, it is represented here that the interface 37 can be configured as a VDI40 receptacle in a preferred configuration. However, in an equally preferred configuration, it can alternatively be configured in particular as a steep taper interface, Morse taper interface, HSK interface or in another suitable manner.

[0087] FIG. 7 shows a representation of a workpiece 39 for machining with the cutting insert 1 according to FIG. 1 and the cutting insert holder according to FIG. 4. The workpiece 39 is configured in particular as a toothed shaft. By means of the cutting insert 1, in particular the first cutting insert 1.1 and the second cutting insert 1.2, in particular by means of the cutting insert kit 27, in particular by means of the cutting insert holder 29, a recess 40, in particular a ring groove 41, in particular a Seegering groove, is preferably made in the workpiece 39. This results in a special way in the advantages described above, since a high stability is important for the cutting inserts 1.1, 1.2 especially due to the discontinuous cutting conditions prevailing in the area of the toothing, and burr formation takes place to a special degree.

[0088] FIG. 8 shows a schematic representation of an embodiment of a method for producing a recess 40, in particular a groove, in particular the ring groove 41 in the workpiece 39 according to FIG. 7.

[0089] During the method, the workpiece 39 is first pre-machined by grooving a preliminary recess comprising a first width with the first cutting insert 1.1, which comprises the first working width B1, which is also referred to as roughing. In this process, a relative rotation of the workpiece 39 to the first cutting insert 1.1, in particular to a tool 43, in particular to the cutting insert holder 29, is effected with a first direction of rotation. In particular, the workpiece 39 is preferably arranged for this purpose in the region of the central axis M of the cutting insert holder 29, wherein first the first cutting insert 1.1 is fedin the radial directiontowards the workpiece 39.

[0090] Then the workpiece is finish-machined by extending the preliminary recess to a second width, which is greater than the first width, with the second cutting insert 1.2, which comprises the second working width B2, which is also referred to as finishing. This is possible because the second working width B2 is larger than the first working width B1. In this way, the recess 40, in particular the ring groove 41, is produced. During finishing, a relative rotation of the workpiece 39 with respect to the second cutting insert 1.2 is effected with a second direction of rotation which is opposite to the first direction of rotation of roughing. In particular, the relative rotation with the second sense of rotation is effected relative to the same tool 43, in particular to the cutting insert holder 29, relative to which the first relative rotation with the first sense of rotation was also effected. The resulting recess 40, in particular the ring groove 41, is deburred during finishing, i.e. finishing, by means of the second cutting insert 1.2, in particular with its deburring cutting edge 15.2. This is done particularly efficiently because the burr is cut off in the opposite direction to its direction of origin. For finish machining, the second cutting insert 1.2 is fedin the radial directiontowards the workpiece 39.

[0091] The relative rotations are effected in particular between the cutting insert holder 29 and the workpiece 39 in each case. Since the cutting inserts 1.1, 1.2 are arranged with reversed orientation on the cutting insert holder 29, it is possible to reverse the direction of relative rotation between pre-machining with the first cutting insert 1.1 and finish machining with the second cutting insert 1.2, so that the burr can be cut off against its direction of origin. In particular, during pre-machining, only the first cutting insert 1.1 is engaged with the workpiece 39, while the second cutting insert 1.2 is not engaged with the workpiece 39. During finish machining, only the second cutting insert 1.2 is in engagement with the workpiece 39, while the first cutting insert 1.1 is not in engagement with the workpiece 39.

[0092] The recess 40, in particular the ring groove 41, is introduced into the workpiece 39 preferably in a hardened or quenched and tempered condition. The workpiece 39 preferably comprises a hardness of at least 36 HRC to at most 60 HRC.

[0093] Preferably, the process is carried out on a vertical lathe, on a horizontal lathe or on a machining center.