MILLING TOOL HOLDER AND MILLING TOOL

Abstract

Milling tool holder which comprises a first holder part, a second holder part, and a locking mechanism. The first holder part comprises a first cutting insert receptacle for receiving a first cutting insert and a second cutting insert receptacle for receiving a second cutting insert. The second holder part which, for adjusting a milling width, is variably positionable with respect to the first holder part along a longitudinal axis, comprises a third cutting insert receptacle for receiving a third cutting insert and a fourth cutting insert receptacle for receiving a fourth cutting insert. The locking mechanism is configured to fix the first and second holder parts to the adjusted milling width. The first holder part and the second holder part are positioned with respect to one another in such a manner that the third cutting insert receptacle is arranged in the circumferential direction between the first cutting insert receptacle and the second cutting insert receptacle, and that the second cutting insert receptacle is arranged in the circumferential direction between the third cutting insert receptacle and the fourth cutting insert receptacle.

Claims

1. A milling tool holder, comprising: a first holder part having a first cutting insert receptacle which is configured to receive a first cutting insert and having a second cutting insert receptacle which is configured to receive a second cutting insert; a second holder part which is variably positionable with respect to the first holder part along a longitudinal axis in order to adjust a milling width, wherein the second holder part comprises a third cutting insert receptacle for receiving a third cutting insert and a fourth cutting insert receptacle for receiving a fourth cutting insert; a spacer element which is arranged between the first holder part and the second holder part and which is configured for adjusting the milling width; a locking mechanism which is configured to fix the first and second holder parts to the adjusted milling width, wherein the first holder part and the second holder part are positioned with respect to one another in such a manner that the third cutting insert receptacle is arranged in the circumferential direction between the first cutting insert receptacle and the second cutting insert receptacle, and in that the second cutting insert receptacle is arranged in the circumferential direction between the third cutting insert receptacle and the fourth cutting insert receptacle, wherein the first holder part comprises a first cylinder surface which is configured to center the spacer element, wherein the first cylinder surface extends symmetrically to the longitudinal axis, and wherein the second holder part comprises a second cylinder surface which is configured to center the spacer element, wherein the second cylinder surface extends symmetrically to the longitudinal axis.

2. The milling tool holder as claimed in claim 1, wherein the spacer element is configured as a sleeve.

3. The milling tool holder as claimed in claim 1, wherein the spacer element comprises a first thread which corresponds with a second thread arranged in the first holder part, wherein the milling width can be adjusted by means of an interaction between the first thread and the second thread.

4. The milling tool holder as claimed in claim 1, wherein the spacer element contacts the second holder part along an annular contact surface.

5. The milling tool holder as claimed in claim 4, wherein the annular contact surface is arranged perpendicularly to the longitudinal axis.

6. The milling tool holder as claimed in claim 1, wherein the spacer element comprises a third cylinder surface which corresponds to the first cylinder surface of the first holder part, wherein a clearance fit is provided first and the third cylinder surface.

7. The milling tool holder as claimed in claim 1, wherein the spacer element comprises a fourth cylinder surface which corresponds to the second cylinder surface of the second holder part, wherein a clearance fit is provided second and the fourth cylinder surface.

8. The milling tool holder as claimed in claim 1, wherein the first cylinder surface and the second cylinder surface are offset with respect to one another along the longitudinal axis and extend coaxially with respect to one another.

9. The milling tool holder as claimed in claim 1, wherein the locking mechanism comprises a screw which is inserted through the spacer element into a third thread which is arranged in the first holder part.

10. The milling tool holder as claimed in claim 9, wherein the screw contacts the first holder part and the second holder part but not the spacer element.

11. The milling tool holder as claimed in claim 10, wherein the screw contacts the second holder part along a conical surface.

12. The milling tool holder as claimed in claim 1, comprising an adjustment adapter which is configured for adjusting the position of the spacer element, wherein the spacer element comprises a first tool engagement which matches the adjustment adapter, and wherein the adjustment adapter additionally comprises a second tool engagement.

13. The milling tool holder as claimed in claim 1, wherein the first holder part and the second holder part contact one another along multiple torque driving faces which correspond with one another, wherein the torque driving faces enclose an angle of less than 5 with a radial direction which extends perpendicularly with respect to the longitudinal axis and to the circumferential direction.

14. A milling tool holder, comprising: a first holder part having a first cutting insert receptacle which is configured to receive a first cutting insert and having a second cutting insert receptacle which is configured to receive a second cutting insert; a second holder part which is variably positionable with respect to the first holder part along a longitudinal axis in order to adjust a milling width, wherein the second holder part comprises a third cutting insert receptacle for receiving a third cutting insert and a fourth cutting insert receptacle for receiving a fourth cutting insert; a spacer element which is arranged between the first holder part and the second holder part and which is configured for adjusting the milling width; a locking mechanism which is configured to fix the first and second holder parts to the adjusted milling width, wherein the first holder part and the second holder part are positioned with respect to one another in such a manner that the third cutting insert receptacle is arranged in the circumferential direction between the first cutting insert receptacle and the second cutting insert receptacle, and in that the second cutting insert receptacle is arranged in the circumferential direction between the third cutting insert receptacle and the fourth cutting insert receptacle, and wherein the spacer element comprises a first annular contact surface which abuts the second holder part and is arranged perpendicularly to the longitudinal axis.

15. The milling tool holder as claimed in claim 14, wherein the second holder part comprises a second annular contact surface which corresponds to the first annular contact surface and contacts said first annular contact surface.

16. The milling tool holder as claimed in claim 15, wherein the second annular contact surface is arranged perpendicularly to the longitudinal axis.

17. A milling tool, comprising: a first holder part having a first cutting insert receptacle which is configured to receive a first cutting insert and having a second cutting insert receptacle which is configured to receive a second cutting insert; a second holder part which is variably positionable with respect to the first holder part along a longitudinal axis in order to adjust a milling width, wherein the second holder part comprises a third cutting insert receptacle for receiving a third cutting insert and a fourth cutting insert receptacle for receiving a fourth cutting insert; a spacer element which is arranged between the first holder part and the second holder part and which is configured for adjusting the milling width; a locking mechanism which is configured to fix the first and second holder parts to the adjusted milling width; a first cutting insert which is arranged in the first cutting insert receptacle; a second cutting insert which is arranged in the second cutting insert receptacle; a third cutting insert which is arranged in the third cutting insert receptacle; a fourth cutting insert which is arranged in the fourth cutting insert receptacle wherein the first holder part and the second holder part are positioned with respect to one another in such a manner that the third cutting insert is arranged in the circumferential direction between the first cutting insert and the second cutting insert, and in that the second cutting insert is arranged in the circumferential direction between the third cutting insert and the fourth cutting insert, wherein the first holder part comprises a first cylinder surface which is configured to center the spacer element, wherein the first cylinder surface extends symmetrically to the longitudinal axis, and wherein the second holder part comprises a second cylinder surface which is configured to center the spacer element, wherein the second cylinder surface extends symmetrically to the longitudinal axis.

18. The milling tool as claimed in claim 17, wherein the first and the second cutting inserts protrude from the first holder part in a first direction which is parallel to the longitudinal axis, and wherein the third and the fourth cutting inserts protrude from the second holder part in a second direction which is in an opposite direction to the first direction.

19. A milling tool, comprising: a first holder part having a first cutting insert receptacle which is configured to receive a first cutting insert and having a second cutting insert receptacle which is configured to receive a second cutting insert; a second holder part which is variably positionable with respect to the first holder part along a longitudinal axis in order to adjust a milling width, wherein the second holder part comprises a third cutting insert receptacle for receiving a third cutting insert and a fourth cutting insert receptacle for receiving a fourth cutting insert; a spacer element which is arranged between the first holder part and the second holder part and which is configured for adjusting the milling width; a locking mechanism which is configured to fix the first and second holder parts to the adjusted milling width; a first cutting insert which is arranged in the first cutting insert receptacle; a second cutting insert which is arranged in the second cutting insert receptacle; a third cutting insert which is arranged in the third cutting insert receptacle; a fourth cutting insert which is arranged in the fourth cutting insert receptacle wherein the first holder part and the second holder part are positioned with respect to one another in such a manner that the third cutting insert is arranged in the circumferential direction between the first cutting insert and the second cutting insert, and in that the second cutting insert is arranged in the circumferential direction between the third cutting insert and the fourth cutting insert, and wherein the spacer element comprises a first annular contact surface which abuts the second holder part and is arranged perpendicularly to the longitudinal axis.

20. The milling tool as claimed in claim 19, wherein the first and the second cutting inserts protrude from the first holder part in a first direction which is parallel to the longitudinal axis, and wherein the third and the fourth cutting inserts protrude from the second holder part in a second direction which is in an opposite direction to the first direction.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0069] FIG. 1 shows a perspective view of an exemplary embodiment of the milling tool;

[0070] FIG. 2 shows an exploded representation of the exemplary embodiment shown in FIG. 1;

[0071] FIG. 3 shows a further perspective view of the exemplary embodiment shown in FIG. 1 in a first state;

[0072] FIG. 4 shows a sectional view of the exemplary embodiment shown in FIG. 1 in the first state;

[0073] FIG. 5 shows a perspective view of the exemplary embodiment shown in FIG. 1 in a second state;

[0074] FIG. 6 shows a sectional view of the exemplary embodiment shown in FIG. 1 in the second state;

[0075] FIG. 7 shows a perspective view of the exemplary embodiment shown in FIG. 1 in a third state;

[0076] FIG. 8 shows a sectional view of the exemplary embodiment shown in FIG. 1 in the third state;

[0077] FIG. 9 shows a perspective view of the exemplary embodiment shown in FIG. 1 in a fourth state; and

[0078] FIG. 10 shows a sectional view of the exemplary embodiment shown in FIG. 1 in the fourth state.

DESCRIPTION OF PREFERRED EMBODIMENTS

[0079] FIGS. 1-10 show various views and different states of an exemplary embodiment of the milling tool. The illustration of the different states serves for explaining the function of the milling tool. The milling tool is designated in each of FIGS. 1-10 overall by way of the reference numeral 100.

[0080] The milling tool 100 comprises a milling tool holder 10 and multiple cutting inserts 12 which are arranged on the milling tool holder 10. Four of said cutting inserts are provided as an example in FIG. 1 with the reference symbols 12a-12d. Purely for the purposes of explanation, said cutting inserts are numbered consecutively as follows: The cutting insert 12a is designated as the first cutting insert, the cutting insert 12b is designated as the second cutting insert, the cutting insert 12c is designated as the third cutting insert and the cutting insert 12d is designated as the fourth cutting insert.

[0081] In the exemplary embodiment shown in the present case, a total of fourteen of said cutting inserts 12 are arranged on the milling tool holder. The minimum number of cutting inserts 12 necessary for the method of operation is, however, only four. In principle, however, the milling tool 100 can comprise any arbitrary number of cutting inserts 12 greater than four. The milling tool 100 preferably comprises an even number of cutting inserts 12.

[0082] According to the present exemplary embodiment, the cutting inserts 12 are fastened releasably on the milling tool holder 10 by means of fastening screws 14 (see FIG. 2). The cutting inserts 12 are arranged releasably in cutting insert receptacles 13 provided for this purpose, only four of said cutting insert receptacles 13a-13d being provided once again as examples with reference symbols in FIG. 2. In an equivalent manner to the naming of the cutting inserts 12a-12d, the cutting insert receptacles 13a-13d in the present case are also designated as follows: First cutting insert receptacle 13a, second cutting insert receptacle 13b, third cutting insert receptacle 13c and fourth cutting insert receptacle 13d.

[0083] However, it is also equally conceivable for the cutting inserts 12 to be fastened releasably or permanently to the milling tool holder 10 in another manner, for example by clamping, soldering or welding. Irrespective of the type of fastening, the cutting inserts 12 are preferably produced from hard metal, the milling tool holders 10, in contrast, preferably from steel.

[0084] The milling tool holder 10 is designed with multiple parts. It comprises a first holder part 16 and a second holder part 18. The two holder parts 16, 18 are movable with respect to one another. This is not naturally the case in the mounted state. The two holder parts 16, 18, however, can be positioned with respect to one another in different positions which are choosable by the user for adjusting the milling width. By means of a locking mechanism 20 which comprises a clamping screw 22 in the present case, the two holder parts 16, 18 can be fixed or secured with respect to one another in the desired position (corresponding to the milling width set). The distance between the two holder parts 16, 18 can preferably be adjusted in a stepless manner.

[0085] In the present exemplary embodiment, a spacer element 24 serves for adjusting the milling width, that is to say for varying the relative position between the two holder parts 16, 18. In the exemplary embodiment shown in the present case, said spacer element 24 is designed as a sleeve which can be screwed into the first holder part 16. As can be seen, in particular, in FIGS. 3-10 and is explained in detail below, the distance between the first holder part 16 and the second holder part 18 is reduced the further the spacer element 24 is screwed into the first holder part 16. This results then in a correspondingly smaller milling width during the use of the milling tool 100. The further the spacer element 24 is screwed out of the first holder part 16, conversely, the greater the distance between the first holder part 16 and the second holder part 18 and accordingly the greater the milling width set.

[0086] The milling tool 100 is usually clamped in a tool receptacle provided for this purpose. To this end, the first holder part 16 comprises a connecting flange 26 at its lower end. Said connecting flange 26 serves together with a fastening screw 28 and an associated washer 30 for fastening or fixing the milling tool 100 to the tool receptacle.

[0087] In particular as a result of the connecting flange 26, the first holder part 16 has a substantially elongated form which corresponds quite roughly in cross section to a T-shaped form. The second holder part 18, in contrast, is designed to be substantially disk-shaped. It is placed onto the top side of the first holder part 16. As will be explained in more detail again later, the second holder part 18 does not rest directly, however, on the first holder part 16 in the axial direction but on the spacer element 24.

[0088] Both holder parts 16, 18, as also the entire milling tool 100, are preferably symmetrical to a longitudinal axis 32. The two holder parts 16, 18 are nested in one another in the mounted state. It could also be said they engage in one another similarly to gearwheels. When viewed in the circumferential direction 34, that is to say around the longitudinal axis 32, a cutting insert receptacle 13 which is associated with the second holder part 18 is arranged in each case between two cutting insert receptacles 13 arranged on the first holder part 16. Conversely, a cutting insert receptacle 13 which is associated with the first holder part 16 is also arranged in each case between two cutting insert receptacles 13 of the second holder part 18. Thus, for example, the third cutting insert receptacle 13c is arranged in the circumferential direction between the first cutting insert receptacle 13a and the second cutting insert receptacle 13b, the third cutting insert receptacle 13c being associated with the second holder part 18 and the first and second cutting insert receptacles 13a, 13b being associated with the first holder part 16. In the same way, the second cutting insert receptacle 13b which is associated with the first holder part 16 is arranged between the third cutting insert receptacle 13c and the fourth cutting insert receptacle 13d which are associated with the second holder part 18. Torque-driving faces 36 which are arranged on the first holder part 16 and correspond with corresponding torque-driving faces 38 which are arranged on the second holder part 18 take care of the torque transmission from the first holder part 16 to the second holder part 18. Said torque-driving faces 36, 38 which correspond with one another preferably extend along a radial direction 40 of the tool 100 which is arranged perpendicularly to the longitudinal axis 32 and perpendicularly to the circumferential direction 34. The torque-driving faces 36, 38 enclose with said radial direction 40 at least an angle <5. In relation to the longitudinal axis 32, the torque driving faces 36, 38 extend either parallel thereto or they are inclined slightly thereto.

[0089] The cutting inserts 12 arranged on the first holder part 16 protrude from the head part of the milling tool holder 10 in a different direction in relation to the cutting inserts 12 arranged on the second holder part 18. The first and the second cutting inserts 12a, 12b, which are arranged on the first holder part 16, protrude, for example, downward from the head part of the milling tool holder 10, whereas the third and fourth cutting inserts 12c, 12d, which are arranged on the second holder part 18, protrude upward from the head part of the milling tool holder 10. In the present case, the terms downward and upward mean two directions which are aligned in opposite directions to one another and are parallel to the longitudinal axis 32. Slightly different cutting inserts are used for the cutting inserts 12 arranged on the first holder part 16 than for the second holder part 18. The cutting inserts arranged on the two holder parts 16, 18 are certainly basically the same as regards type, however they are designed in a mirror-inverted manner to one another. In technical jargon in this respect, they are mostly referred to as left and right cutting inserts which are arranged in the present case in alternate rows on the first and on the second holder parts 16, 18. It should also be noted at this point that the cutting inserts 12 in the present case are arranged tangentially to the two holder parts 16, 18. However, this is not absolutely. The cutting inserts 12 can also be arranged just as well axially or in another alignment on the milling tool holder 10 without departing from the spirit and scope of the disclosure.

[0090] FIGS. 3 and 4 show a first state of the milling tool 100 where the milling width is set to the smallest value, that is to say the distance between the first holder part 16 and the second holder part 18 is as small as possible, and where the two holder parts 16, 18 are fixed by means of the locking mechanism 20 or the clamping screw 22. The clamping screw 22, in this case, presses with its conically formed head against a correspondingly formed conical surface 42 of the second holder part 18. As a result, the clamping screw 22 exerts force onto the second holder part 18 both in the axial direction and the radial direction. The spacer element 24 is not contacted, however, by the clamping screw 22. The clamping screw 22, without touching the spacer element 24, is screwed through the spacer element 24 into the first holder part 16. To this end, an external thread 44 which corresponds with an internal thread 46 provided in the interior of the first holder part 16, is provided on the underside of the clamping screw 22. Both threads 44, 46 are preferably designed as fine-pitch thread.

[0091] The spacer element 24 is also screwed into the first holder part 16 in the exemplary embodiment shown in the present case. To this end, an external thread 48, which corresponds with an internal thread 50 arranged in the interior of the first holder part 16, is provided on the lower end of the spacer element 24. For simpler differentiation, the thread 44-50 will be designated as follows below: The external thread 48 provided on the spacer element 24 is designated as the first thread. The internal thread 50 provided in the first holder part 16 is designated as the second thread. The internal thread 46 also provided in the first holder part 16 is designated as the third thread. The external thread 44 arranged on the clamping screw 22 is designated as the fourth thread. All threads 44-50 are preferably fine-pitch thread. The threads 46, 50 (second and third threads) provided in the first holder part 16 preferably extend coaxially but are offset to one another along the longitudinal axis 32.

[0092] In the mounted state, the clamping screw 22 presses among others in the axial direction against the second holder part 18. The second holder part 18 rests on the spacer element 24 in the axial direction. To this end, spacer element 24 and second holder part 18 each comprise an annular contact surface 52, 54, along which said two components contact one another. The annular contact surfaces 52, 54 serve as axial planar support. This serves substantially for the purpose of minimizing wobble errors.

[0093] The spacer element 24, as already mentioned, is screwed into the first holder part 16. In the state shown in FIG. 4, the spacer element 24 is screwed in fully up to a lower stop 56 which is provided for this purpose in the interior of the first holder part 16. In order to be able to keep the axial run-out tolerance and the concentricity tolerance of the milling tool 100 as small as possible, a clearance fit which functions as a centering means is provided in each case in the radial direction between the spacer element 24 and the first holder part 16 and also between the spacer element 24 and the second holder part 18. A cylinder surface 58 which extends symmetrically to the longitudinal axis 32 and in the present case is designated as the first cylinder surface, is provided for this purpose in the first holder part 16. Said first cylinder surface 58 corresponds with a cylinder surface 60 provided on the outer circumference of the spacer element 24. A cylinder surface 62 which extends symmetrically to the longitudinal axis 32 is provided in a similar manner on the second holder part 18 further at the top in FIG. 4. Said cylinder surface 62 is designated as the second cylinder surface in the present case. It corresponds with a cylinder surface 64 provided on the outer circumference of the upper end of the spacer element 24. A clearance fit is preferably provided between the cylinder surfaces 58, 60 and also between the cylinder surfaces 62, 64. The first cylinder surface 58 preferably extends coaxially to the second cylinder surface 62, the two cylinder surfaces 58, 62 being arranged offset to one other axially when the tool is in the mounted state.

[0094] In order to modify the distance between the two holder parts 16, 18 and consequently the milling width, the spacer element 24 has to be moved into another position in relation to the first holder part 16 by screw connection. This operation is shown as an example in FIGS. 5-8. An adjustment adapter 66 is used here to screw-in or screw-out the spacer element 24. Figs.5 and 6 show the state in which the spacer element 24 is (still) screwed fully into the first holder part 16. FIGS. 7 and 8 show, in contrast, the state in which the spacer element 24 has already been screwed out of the first holder part 16 in part so that the milling width or the distance between the two holder parts 16, 18 is enlarged.

[0095] The adjustment adapter 66 engages in a tool engagement 68 which is arranged in the region of the upper end on the inside of the spacer element 24. In the present case, this is a multifaceted tool engagement. Said tool engagement 68 is designated in the present case as the first tool engagement. In the interior of the adjustment adapter 66, a second tool engagement 70 is furthermore provided, by means of which the adjustment adapter 66 can be moved. In the present case, this is designed as an Allen tool engagement. By inserting an Allen key into the second tool engagement 70, the adjustment adapter 66 and consequently also the spacer element 24 can consequently be moved very simply. It should be noted, however, at this point that other types of tool engagements for the tool engagements 68, 70 can obviously also be used without departing from the spirit and scope of the present disclosure. In principle, it is also possible to screw the spacer element 24 by hand into the holder part 16 or to screw it by hand out of said holder part.

[0096] As soon as the desired milling width or the desired distance between the two holder parts 16, 18 is set, the two holder parts 16, 18 can be fixed again by means of the locking mechanism 20. This is shown in FIGS. 9 and 10. The state shown in FIGS. 9 and 10 corresponds therefore, once again, to the mounted state which is also shown in FIGS. 3 and 4, the distance between the two holder parts 16, 18 being enlarged in comparison thereto.

[0097] Finally, it should be mentioned that, in principle, another type of locking mechanism can be used in place of the clamping screw 22 used in the exemplary embodiment shown as an example in the present case. For example, a clamping mechanism could also be used for this purpose.