Milling tool

Abstract

A milling tool (100) comprising a milling tool body (10) having a first end (11) with an interface for connection to a tool receptacle on the machine side and a free second end (12) having at least one seat (13) for receiving an exchangeable cutting insert (1), wherein on the seat (13) there are arranged a first support member (21) for supporting a first side surface of the cutting insert (1), the first support member (21) being reversibly attached to the milling tool body (10) by a first attachment member (21a), a second support member (22a) for supporting a second side surface of the cutting insert (1), the second support member (22) being reversibly attached to the milling tool body (10) by a second attachment member (22a), and a third support member (23a) for supporting a lower side surface of the cutting insert (1), the third support member (23) being reversibly attached to the milling tool body (10) by a third attachment member (23a).

Description

Technical Field

[0001] The present invention relates to a milling tool having a milling tool body with a first end having an interface for connection to a tool receptacle on the machine side and a free second end having at least one seat for receiving an exchangeable cutting insert.

Background Art

[0002] Milling tools are often used, particularly for machining metallic materials or, for example, composite materials. Such tools have a milling tool body, with an exchangeable cutting insert arranged at its free end, which insert has cutting edges that engage the material to be machined. In this case, the milling tool body is typically made of a relatively tough material, such as tool steel for example, and the exchangeable cutting insert is formed from a significantly harder material, such as hard metal (cemented carbide), cermet or cutting ceramic for example. Depending on the material to be machined, superhard cutting materials such as polycrystalline diamond (PKD) or cubic boron nitride (CBN) are partly used for the cutting edge.

[0003] The exchangeable cutting insert is typically held in a seat formed on the outer circumference of the milling tool body. To reversibly attach the cutting insert, fastening screws passing through through-holes in the respective cutting inserts are partly used or so-called clamp jaws or clamping wedges are used, which act by frictional force on one side of the respective cutting insert and, in some cases, also by a fitting force.

[0004] In order to enable adjustment of the position of the cutting insert in particular, it is sometimes done, for example, not to fix the cutting insert directly to the seat on the milling tool body, but to fix it to the cutting insert seat of an exchangeable cassette and then to the milling tool body. In such an embodiment, the exchangeable cutting insert is usually abutted against the corresponding lateral bearing surfaces of the cassette via at least two sides, and in many cases the lower part is also supported by the cassette.

[0005] In the case of a milling tool, especially for heavy cutting, large forces act during operation, so that the cutting insert may break. In this case, damage often also occurs in the area adjacent to the seat and / or in the cassette in which the cutting insert is held, which involves relatively high costs. Furthermore, in known milling tools, in most cases it is not possible to use different types of exchangeable cutting inserts or a great deal of effort is required for the exchange.

Summary of the Invention

Problems to be Solved by the Invention

[0006] The object of the present invention is to provide an improved milling tool in which the cost in the case of damage to the exchangeable cutting insert is reduced and which can be easily converted to various exchangeable cutting inserts.

Means for Solving the Problems

[0007] This problem is solved by the milling tool according to claim 1. Advantageous embodiments are described in the dependent claims.

[0008] The milling tool has a milling tool body, which has a first end with an interface for connecting to the tool receptacle on the machine side and a free second end with at least one seat for accommodating an exchangeable cutting insert. Arranged in the seat are a first support member that is reversibly attached to the milling tool body by a first attachment member and supports a first side of the cutting insert, a second support member that is reversibly attached to the milling tool body by a second attachment member and supports a second side of the cutting insert, and a third support member that is reversibly attached to the milling tool body by a third attachment member and supports the underside of the cutting insert.

[0009] By means of the first, second, and third support members, which are supplied separately from one another and are reversibly attached to the milling tool body by the respectively assigned attachment members, in the event of damage to the exchangeable cutting insert, it is possible to replace only the similarly damaged area, for example one of the support members. Furthermore, by replacing one or more support members, the seat can be converted in a particularly simple manner so as to accommodate exchangeable cutting inserts having different shapes.

[0010] According to one embodiment, the first, second, and third attachment members are each formed as a screw. In this case, particularly easy handling is possible.

[0011] According to one embodiment, the first, second, and third attachment members are each formed with an engagement area for a screw tool, and these engagement areas are designed to engage with the same screw tool. In this case, the milling tool is designed to be particularly user-friendly and it is not necessary to provide a large number of different screw tools.

[0012] According to one embodiment, a clamping wedge for applying a clamping force to the upper side of the cutting insert is arranged in the area of the seat. In this case, particularly firm and reliable fixing of the cutting insert to the milling tool body is ensured.

[0013] According to one embodiment, the clamping wedge is connected to the milling tool body by a screw member. This enables a particularly simple and user-friendly operation for replacing the cutting insert. The screw member can preferably have an engagement area for a screw tool, which allows the same screw tool to be used for each mounting member of the support member.

[0014] According to one embodiment, the screw member has a first thread region that interacts with the thread portion within the clamping wedge and a second thread region that interacts with the thread portion within the milling tool body. In this case, a particularly simple operation of the clamping wedge by the screw member is enabled.

[0015] According to one embodiment, the first thread region and the second thread region of the screw member are made to be different from each other in the direction of rotation of the thread and / or the pitch of the thread. This provides a particularly simple and reliable way of moving the clamping wedge for attaching and releasing the replaceable cutting insert.

[0016] According to one embodiment, the third support member is horizontally supported on the first support member and the second support member respectively. In this case, on the one hand, the third support member can be replaced particularly easily, and on the other hand, a particularly compact and robust attachment of the cutting insert is achieved.

[0017] According to one embodiment, the third mounting member is arranged obliquely such that the third support member is tensioned in the direction of the first support member and the direction of the second support member. This allows good access to the third mounting member, and the cutting insert is supported particularly firmly and reliably.

[0018] According to one embodiment, there is provided a first set consisting of a first support member, a second support member, and a third support member, and at least one further set different from the first set, consisting of a first support member, a second support member, and a third support member for adapting the seat to receive different cutting inserts. In this case, all the support members of the further set may be different from the corresponding support members in the first set, for example, or only one or two of the support members may be different from the corresponding support members in the first set. When the support members of the first set and the support members of at least one further set are provided, the modification to different types of replaceable cutting inserts can be carried out particularly easily and quickly.

[0019] According to one embodiment, a plurality of seats are provided at the second end, distributed across the outer periphery of the milling tool body for receiving replaceable cutting inserts. In this case, the seats can all be designed in the same way, in particular. The seats can preferably be designed to accommodate the same cutting insert in the same direction. In this case, a particularly efficient cutting process becomes possible.

[0020] When the first support member and the second support member have the same design, particularly simple and easy-to-use operation becomes possible, and the manufacturing cost can be kept low.

[0021] According to one embodiment, the seats on the milling tool body are completely formed by hobbing from one machining direction. In this case, particularly cost-effective manufacturing becomes possible.

Brief Description of the Drawings

[0022] Further advantages and advantageous features of the present invention will be made apparent by the following description of exemplary embodiments with reference to the accompanying drawings.

[0023]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

[0024] Referring to Figs. 1 to 10, an embodiment of the milling tool will be described in more detail below.

[0025] In particular, as can be seen in FIGS. 1 to 3, the milling tool 100 in the illustrated embodiment is designed as a so-called insert-type milling cutter and has a corresponding interface for connecting to the drive unit of a machine tool. In this embodiment, such a design is shown in the form of an insert-type milling cutter, but the milling tool 100 can also be provided with any other conventional interface.

[0026] The milling tool 100 has a milling tool body 10 which can be formed, for example, from tool steel. The milling tool body 10 has a first end 11 provided with an interface 11a for connecting to the drive device of a machine tool and a free second end 12. A plurality of seats 13 for receiving the replaceable cutting inserts 1 are formed at the free second end 12 of the cutting tool body 10.

[0027] In this embodiment, a total of 12 such seats 13 are provided, but depending on the application, fewer than 12 seats 13 or more than 12 seats 13 may be provided. The seats 13 are distributed and arranged on the outer circumference of the milling tool body 10 at the free second end 12, and the cutting inserts 1 arranged in the seats each project axially and radially from the milling tool body 10 in the active cutting edge region, as seen from the rotation axis Z of the milling tool 100. In the illustrated embodiment, the seats 13 are arranged so as to be substantially uniformly distributed over the outer circumference and are designed to accommodate the same cutting inserts 1.

[0028] A chip groove 14 for discharging the chips generated during the operation of the milling tool 100 is formed adjacent to the seats 13 of the milling tool body 10.

[0029] In particular, as can be seen in the enlarged detailed view of the area of the seat portion 13 in FIG. 4, a first support member 21 for supporting the first side surface of the cutting insert 1 on the milling tool body 10 is arranged in the area of the seat portion 13. The first support member 21 is reversibly attached to the milling tool body 10 by a first attachment member 21a. In this embodiment, the first attachment member 21a is formed as a screw, and the screw portion penetrates through the through hole of the first support member 21 and engages with a corresponding screw hole 21b formed in the milling tool body 10 as shown in FIG. 7. Here, the head of the first attachment member 21a is supported by the inner wall of the through hole of the first support member 21, and is configured to pull the support member against the milling tool body 10. An engagement area for a screw tool is provided on the head of the first attachment member 21a, and the first attachment member 21a is operated by this engagement area. Although a specific design embodiment of the engagement area is shown as an example, the engagement area can also be designed in other ways, for example, in the form of a hexagonal socket, a cross-shaped head, etc.

[0030] Furthermore, a second support member 22 for supporting a second side surface different from the first side surface of the cutting insert 1 is arranged in the area of the seat portion 13 of the milling tool body 10. The second support member 22 is reversibly fastened to the milling tool body 10 by a second attachment member 22a. In this embodiment, the second attachment member 22a is also formed as a screw, and the screw portion penetrates through the through hole of the second support member 22 and engages with a corresponding screw hole 22b formed in the milling tool body 10 as shown in FIG. 7. The head of the second attachment member 22a is supported by the inner wall of the through hole of the second support member 22, and is configured to apply tension to the milling tool body 10. An engagement area for a screw tool capable of operating the second attachment member 22a is provided on the head of the second attachment member 22a. In this embodiment, the engagement area of the second attachment member 22a has the same design as the engagement area of the first attachment member 21a, and as a result, the same screw tool can be used for its operation.

[0031] Furthermore, a third support member 23 for supporting the back surface of the cutting insert 1 is disposed in the region of the seat portion 13 of the milling tool body 10. The third support member 23 is reversibly fastened to the milling tool body 10 by a third attachment member 23a. In this embodiment, the third attachment member 23a is likewise formed as a screw, the threaded portion of which penetrates through the through-hole of the third support member 23 and engages with a threaded hole 23b formed in the milling tool body 10 as shown in FIG. 7. The head of the third attachment member 23a is supported by the inner wall of the through-hole of the third support member 23 and is adapted to apply tension to the milling tool body 10. An engagement region for a screw tool capable of operating the third attachment member 23a is provided on the head of the third attachment member 23a. In this embodiment, the engagement region of the third attachment member 23a has the same design as the engagement regions of the first attachment member 21a and the second attachment member 22a, so that the same screw tool can be used for their operation in each case.

[0032] In this embodiment, the third support member 23 is formed as an underplate, the shape of which is adapted to the shape of the cutting insert 1 so as to support the cutting insert substantially completely flat on the seat portion 13. As can be seen particularly in FIGS. 4, 8, 9 and 10, the third support member 23 is supported by the first support member 21 and the second support member 22 in the mounted state. The threaded hole 23b for the third attachment member 23a is designed to be slightly inclined with respect to the bearing surface for the third support member 23 as shown in FIG. 5, and the third support member 23 is tensioned in the direction of the first support member 21 and the direction of the second support member 22 when the third attachment member 23a is tightened. Furthermore, due to the obliquely inclined design of this threaded hole 23b, easy access can be had to the engagement region of the third attachment member 23a to operate the same.

[0033] In this embodiment, the first support member 21 and the second support member 22 have the same design, which further facilitates handling and has a positive effect on the manufacturing cost.

[0034] As can be seen in particular in FIGS. 4, 5 and 9, a clamping wedge 24 is arranged for fixing the cutting insert 1 on the seat 13. The clamping wedge 24 is guided in a gap 25 on the milling tool body 10 and can be actuated by a screw element 24a which fixes the clamping wedge 24 to the milling tool body 10. The clamping wedge 24 has, as a threaded part, a hole with an internal thread, into which the upper shank part of the screw element 24a, provided with a first thread region formed as a corresponding external thread, is received. The milling tool body 10 is provided with a threaded hole as a threaded part, into which the lower shank part of the screw element 24a engages by means of a second thread region formed as a corresponding external thread. When the screw element 24a is actuated, the first thread region and the second thread region of the screw element 24a are embodied such that the direction of rotation of the thread is different, i.e., one of the two thread regions is designed as a left-hand thread and the other is designed as a right-hand thread, so that the clamping wedge 24 can move along the longitudinal axis of the screw element 24a. The same applies to the threaded parts within the clamping wedge 24 and within the milling tool body 10, which interact with the first thread region and the second thread region, respectively.

[0035] The guide surface of the clamping wedge 24 within the gap 25 extends at an angle with respect to the upper side of the third support member 23, so that when the screw element 24a is tightened, the clamping wedge 24 approaches the third support 23, and thus the cutting insert 1 can be fixed. The fixing of the cutting insert 1 can be effected solely by frictional force, for example by applying a clamping force to the upper side of the cutting insert 1, or the surface of the clamping wedge 24 facing the cutting insert 1 can also interact with the upper side of the cutting insert 1 in an engaging fit.

[0036] In this embodiment, the screw element 24a for actuating the clamping wedge 24 is provided with an engagement region for a screw drive tool which enables the same screw drive tool, which can also be used for the clamping elements 21a, 22a and 23a, to be used for actuation, so that a particularly comfortable and simple operation is possible.

[0037] In this embodiment, the movement of the clamping wedge 24 along the longitudinal axis of the screw element 24a is provided by the different rotational directions of the first and second screw regions. However, for example, it is also possible to rotate the first and second screw regions in the same direction and vary the screw pitch.

[0038] As can be seen from FIG. 11, in this embodiment, at least one further set consisting of a first support member 21', a second support member 22' and a third support member 23' is provided, which is different from the first set consisting of the above-described first support member 21, second support member 22 and third support member 23. In this way, the milling tool can be converted very simply and quickly to accept cutting inserts 1 of different shapes and / or dimensions.

[0039] FIG. 12 shows a further set consisting of a first support member 21'', a second support member 22'' and a third support member 23'', which is different from the set of the first, second and third support members described above. The set schematically shown in FIG. 12 is designed to adapt the seat to receive a replaceable cutting insert having a substantially octagonal shape.

[0040] In particular, as can be seen in FIG. 7, the seat 13 of the milling tool body 10 has a shape that is formed entirely by hobbing from one direction.

Claims

1. A milling tool (100) comprising a milling tool body (10) having a first end (11) with an interface for connection to a tool receiving part on the machine side and a free second end (12) having at least one seat (13) for receiving an exchangeable cutting insert (1), on said seat (13), a first support member (21) for supporting a first side surface of said cutting insert (1), said first support member (21) being reversibly attached to said milling tool body (10) by a first attachment member (21a), a second support member (22a) for supporting a second side surface of said cutting insert (1), said second support member (22) being reversibly attached to said milling tool body (10) by a second attachment member (22a), and a third support member (23a) for supporting a lower side surface of said cutting insert (1), said third support member (23) being reversibly attached to said milling tool body (10) by a third attachment member (23a), wherein said members are arranged.

2. The milling tool according to claim 1, wherein said first, second and third attachment members (21, 22, 23) are each formed as a screw.

3. The milling tool according to claim 1 or 2, wherein said first, second and third attachment members (21, 22, 23) each comprise an engagement region for a screw tool, and said engagement regions are set to engage with the same screw tool.

4. The milling tool according to any one of claims 1 to 3, wherein a clamping wedge (24) for applying a clamping force is arranged in the region of said seat above said cutting insert (1).

5. The milling tool according to claim 4, wherein said clamping wedge (24) is connected to said milling tool body (10) by a screw element (24a).

6. The milling tool according to claim 5, wherein said screw element (24a) has a first screw region interacting with a screw part in said clamping wedge (24) and a second screw region interacting with a screw part in said milling tool body (10).

7. The milling tool according to claim 6, wherein said first screw region and said second screw region of said screw element (24a) are different from each other in the rotational direction of the thread and / or the thread pitch.

8. The milling tool according to any one of claims 1 to 7, wherein the third support member (23) is supported on both sides of the first support member (21) and the second support member (22).

9. The milling tool according to any one of claims 1 to 8, wherein the third mounting member (23a) is arranged obliquely so that the third support member (23) is tensioned in the direction of the first support member (21) and the direction of the second support member (22).

10. The milling tool according to any one of claims 1 to 9, wherein at least one further set, different from the first set, consisting of a first support member (21'), a second support member (22') and a third support member (23') is provided to adapt the seat (13) to receive different cutting inserts.

11. The milling tool according to any one of claims 1 to 10, wherein a plurality of seats (13) distributed around the milling tool body (10) are provided at the second end (12) to receive exchangeable cutting inserts (1).

12. The milling tool according to any one of claims 1 to 11, wherein the first support member (21) and the second support member (22) are designed identically.

13. The milling tool according to any one of claims 1 to 12, wherein the seats (13) on the milling tool body (10) are entirely produced by hobbing from one machining direction.

Images