Milling tool, in particular fir tree cutter, and manufacturing process for a milling tool

Abstract

A milling tool (1) designed as an end mill or finishing cutter, manufactured in one piece from a uniform material, preferably a fir tree cutter (1, 1', 1") or a bore cutter, with a working area (3) rotatable about a working axis (4) for milling a workpiece, which has at least one milling edge (5) extending transversely to the circumferential direction (U) of the working axis (4), wherein at least one of the at least one milling edge (5) comprises at least one milling edge section (5.1 - 5.4) in which a milling edge profile (P) defined by the radial distance (F) of the milling edge (5) from the working axis (4) has a non-linear course along the milling edge (5), wherein the milling edge (5) in the milling edge section (5.1 - 5.4) is associated with a chip space (7) extending radially inwards towards the working axis (4) relative to the milling edge (5). is which is in the milling edge section (5.1 - 5-4) with non-linear milling edge profile (P) has a chip space base (9, 10, 10') which follows the milling edge profile (P) at least sectionally, wherein a clearance surface (15) extends to at least one of the at least one milling edge (5) opposite to the working direction of rotation (R) of the milling tool (1), and wherein a pitch angle (T) defined by the milling edges (5) is three to 20 times the circumferential angle associated with the clearance surface (15).

Description

[0001] The invention relates in particular to a milling tool designed as an end mill or finishing mill, in particular a Christmas tree milling cutter, and to a manufacturing method for a milling tool.

[0002] End mills, such as finishing mills, in particular with a fir tree milling profile, as known from US 2011 / 0312253 A1, i.e. so-called fir tree mills, are intended for the flat removal of material from a workpiece surface and are moved for this purpose in a milling movement with rotation of the end mill about its working rotation axis or tool axis with simultaneous feed relative to the workpiece surface.

[0003] End mills typically have an elongated, essentially cylindrical shank along the working axis of rotation, for example, and an adjoining machining head, on whose lateral surface protrude milling cutters (especially milling edges), such as circumferential milling cutters and, if applicable, face-milling cutters. A clamping area for clamping in a tool holder of a machine tool is usually provided on the area of ​​the shank adjacent to the machining head.

[0004] In order to enable surface material removal, the peripheral milling cutting edges or edges can extend continuously and without interruptions on a generally cylindrical surface that is rotationally symmetrical about the working axis of rotation over a certain length transverse to the circumferential direction of the working axis of rotation, so that they can engage in the workpiece surface essentially over their entire axial length with an engagement depth that is radial to the tool axis.

[0005] The axial length of the milling cutters is significantly larger than the radial cutting depth, usually by at least a factor of 5 to 10. While the peripheral milling cutters can also run straight parallel to the tool axis, they are usually spiraled or helical around the tool axis at a helix angle.

[0006] The milling movement produces the discontinuous cut of the milling cutters that is characteristic of milling, which causes chips from the workpiece to be lifted above the surface.

[0007] To produce high-quality surfaces, or high surface qualities, for example, in finish milling, in addition to the precision of the milling tool, the smooth running of the milling tool used is also important. It is particularly advantageous if the geometry and design of the milling tool, especially the machining head, are designed in such a way that oscillations and vibrations are avoided during the milling process, which is usually carried out at comparatively high speeds.

[0008] Apart from that, it is generally desirable for milling tools that the machining area, especially the machining head, is designed in such a way that the best possible service life is achieved.

[0009] WO 2010 / 023760 A1 discloses a milling cutter with a stepped base body to which individual milling blades are mechanically attached. DE 198 55 045 A1 discloses a milling cutter with a similar structure, in which milling teeth or cutting plates are screwed to a fir-tree-shaped base body.

[0010] US 3,678,554 A discloses a toroidal milling cutter in which each tooth of the milling cutter is at the same angle of 15 to 45° relative to the axis of rotation of the milling cutter.

[0011] US 4,243,348 A discloses a holder for milling blades, wherein the milling blades are held and clamped to a base body by screws and clamping jaws.

[0012] Based on this, it is an object of the invention to provide a milling tool, in particular an end mill, finishing mill, in particular a Christmas tree mill, and a corresponding manufacturing method, with which comparatively high surface qualities can be achieved in milling tools, and in which, for example, comparatively long service lives can be achieved, in particular combined with a reduced risk of milling edge breakage.

[0013] This object is achieved by the features of the independent claims. Further developments and refinements emerge from the dependent claims and the following description of exemplary embodiments of the invention.

[0014] The features and feature combinations described herein according to the underlying invention are not limited by the feature combination(s) and the selected references in the claims. Each feature in the claims may be claimed in any combination with one or more other features of the claims or the following description, even independently of the respective references in the claims.Furthermore, each feature disclosed in the following description and / or the appended drawings and / or described or disclosed in connection with the drawings can be claimed on its own, independently or detached from the context in which it appears, alone or in any combination with one or more other features described or disclosed in the claims, the description and / or the drawings, in particular to the extent that the respective feature makes at least a contribution to solving the underlying problem. In particular, each of the embodiments described below or each of the described exemplary embodiments and their features can also be claimed separately and / or in any combination.

[0015] In one embodiment of the invention, in particular according to claim 1, a milling tool designed as an end mill or finishing mill is provided, which is made in one piece from a uniform material and can be designed, for example, as a Christmas tree milling cutter or as a bore milling cutter.

[0016] In a Christmas tree cutter, the milling edges in the machining head are designed to have a Christmas tree-shaped milling edge profile (in particular, a Christmas tree-shaped milling contour), allowing the creation of Christmas tree-shaped milling structures on workpieces. Such milling structures can, for example, have multiple wave crests and wave troughs with varying heights and depths relative to the workpiece surface.

[0017] For example, a Christmas tree cutter can have several milling edges which run in a preferred direction along the tool axis, i.e. working axis of rotation, and in particular transversely to the circumferential direction of the working axis of rotation, wherein each milling edge can have several wave crests and wave troughs which, viewed in the milling profile, form a Christmas tree structure.

[0018] The proposed milling tool is rotatable about a working rotation axis (in particular also: tool axis), in particular in such a way that a milling profile corresponding to the milling edge profile of the working area can be produced on a workpiece.

[0019] The working area can have at least one, preferably several, milling edges extending transversely to the circumferential direction of the working axis of rotation. In other words, the working area can have at least one, preferably several, milling edges, wherein each milling edge, viewed locally parallel to its longitudinal extent, can be oriented transversely to the circumferential direction defined with respect to the working axis of rotation.

[0020] The milling edge(s) running transversely to the working axis of rotation can run in sections, for example, vertically or helically, e.g. at a predetermined angle, in particular helix angle, to the longitudinal axis (in particular: tool axis).

[0021] At least one of the at least one milling edge of the proposed milling tool has at least one milling edge section in which a milling edge profile defined by the radial distance of the milling edge from the working axis of rotation, i.e., by the milling edge radius of the milling edge, has a non-linear profile along the milling edge. In other words, at least one, in embodiments each, of the at least one milling edge has a milling edge profile in at least one milling edge section, which can be defined, for example, by a predetermined longitudinal extension across the working area, which exhibits a profile different from a linear profile.

[0022] Furthermore, it is provided that the milling edge in the milling edge section is assigned a chip space extending (in particular also: recessed) radially inward relative to the milling edge toward the working axis of rotation. The chip space can be defined, for example, as a space locally recessed relative to the milling edge or as a space extending radially inward from the milling edge toward the working axis of rotation, with, for example, a predetermined width or a predetermined width profile in the circumferential direction, or cross-section.

[0023] The chip space can, for example, have a predetermined chip space profile in sections perpendicular to the milling edge, which can be constant or variable along the milling edge. The chip space profile, particularly in its coarse structure, can be designed, for example, in the manner of a U- or V-shape that opens radially outwards.

[0024] The chip space can be designed as a chip space formed radially inwards with respect to the milling edge, ie towards the working rotation axis, in particular as a chip space adjoining the milling edge in the milling edge section radially inwards, ie towards the working rotation axis, for example as a chip space set back radially from the milling edge.

[0025] The chip space has a chip space base, and the chip space is designed such that the chip space base follows the milling edge profile at least in sections in the milling edge section with a non-linear profile, in particular along the length of the milling edge section having the non-linear profile. In particular, in a milling edge section that includes a non-linear milling edge profile section, the profile of the chip space base can follow the profile of the milling edge profile at least in sections.

[0026] Because the chip space base follows the milling edge in the profile at least in sections, for example runs partially parallel to the milling edge or essentially parallel to the milling edge, it can be achieved that at least locally improved strengths and service life for the milling edge and any formed milling teeth can be achieved.

[0027] As mentioned, it can be provided that the chip space base follows the milling edge profile in its course along the milling edge. The chip space base can in particular have a profile, i.e. a chip space base profile, which follows the milling edge profile, in particular corresponds to the milling edge profile and / or is congruent thereto and / or, in particular in its course along the milling edge, follows the milling edge profile in or with respect to the radial direction or runs essentially equidistant from the milling edge profile and / or from the envelope of the milling edge and / or to the milling edge in its course along the milling edge viewed perpendicular to the milling edge or radially with respect to the working rotational axis. In particular, the distance between the milling edge and the chip space base, measured perpendicular to the milling edge, can be essentially constant in at least some sections in the course along the milling edge.Furthermore, it is possible that the radial distance between the milling edge and the chip space base measured with respect to the working rotation axis is essentially constant, at least in sections.

[0028] The milling edge profile and the chip space base profile can, for example, run essentially parallel to one another along the milling edge in the milling edge section, in particular with regard to the coarse structure, for example the envelope, of the milling edge profile.

[0029] In particular, it can be provided that the milling edge section essentially encompasses the entire milling edge, or that the milling edge section of a milling edge extends over the entire length of the milling edge. For example, the chip space can be designed such that the chip space base follows the milling edge profile along the entire milling edge. A milling edge section of a milling edge can be viewed in the longitudinal extension of the milling edge, but can also relate to only a section of the entire milling edge.

[0030] In embodiments, as already mentioned, it can be provided that a radial distance or a distance measured perpendicular to the milling edge between the chip space base and the milling edge is constant in the course along the milling edge, or that a chip surface formed between the chip space base and the milling edge has a substantially constant width, in particular a mean width, measured transversely to the milling edge in the course along the milling edge in the milling edge section.

[0031] A chip space is to be understood in particular as a space upstream of the milling edge in the working direction of rotation, offset radially inwards from the milling edge, for example in the form of a groove, which is designed in particular to receive and / or shape the milling material produced during the milling operation, e.g. chip material.

[0032] The chip space base can be understood, for example, as a line or surface running within the chip space that, along the milling edge, has the smallest radial distance from the working axis of rotation. The chip space base can be understood, for example, as a root line or surface formed in the area of ​​the bottom of the chip space, where the root line could be, for example, the intersection line between two chip faces of the chip space.

[0033] The non-linear course of the milling edge profile and the corresponding chip space base profile formed in the milling edge section of the at least one milling edge can be provided, for example, by a milling edge radius or chip space base radius corresponding to the radial distance of the milling edge or the chip space base from the working rotation axis initially increasing in the milling edge section along the milling edge and then decreasing again and / or that the milling edge profile / chip space base profile, viewed geometrically, has at least one turning point, an extreme point and / or a point of discontinuity in its derivative or gradient, for example a kink, in the milling edge section.

[0034] In embodiments, the milling edge and the chip space base can be designed such that a chip surface formed between the milling edge and the chip space base in the milling edge section has a substantially constant width along the length of the milling edge, in particular measured perpendicular to the milling edge.

[0035] In embodiments, it can be provided that a distance measured radially or perpendicularly to the milling edge between the milling edge and the chip space base is substantially constant or consistent along the milling edge, ie locally along the milling edge, at least within the milling edge section, preferably over the entire milling edge.

[0036] In embodiments, it can be provided that the milling edge profile is designed in such a way that a milling edge radius measured with respect to the working axis of rotation, in particular locally or locally averaged, initially increases and then decreases again along the milling edge, ie in the course along the milling edge.

[0037] The milling edge radius refers specifically to the local distance, measured in the radial direction, between the milling edge and the working axis of rotation. The milling edge profile results from the course of the milling edge radius along the milling edge, which can, for example, reflect the variation of the milling edge radius depending on the axial length along the working axis of rotation.

[0038] In embodiments, the milling edge profile can, when viewed geometrically, have at least one inflection point, one extremum point and / or one discontinuity point in its derivative or gradient, at least within the milling edge section.

[0039] In embodiments, the milling edge profile can be designed such that a distance measured radially or perpendicularly to the milling edge between the milling edge and the chip space base along the milling edge is substantially constant at least within the milling edge section.

[0040] The milling edge profile can in particular be designed such that a chip surface formed between the chip space base and the milling edge in the milling edge section has a substantially constant width in the course of the longitudinal milling edge, in particular measured radially or perpendicularly to the milling edge.

[0041] The at least one milling edge section is designed in particular such that the milling edge radius along the milling edge, ie in the course along the milling edge or in the longitudinal course, is not constant, but varies, for example continuously and / or discontinuously, so that the milling edge profile defined by the milling edge radius in at least one milling edge section in the longitudinal direction of the milling edge, ie in the course along the milling edge, shows a non-linear course as described in more detail above, for example initially increases and then decreases again.

[0042] The milling edge section can, for example, comprise a wave crest or a wave trough, a peak, a notch, a notch, a notch, and the like, or at least partially comprise such a structure such that the associated milling edge profile exhibits the non-linear progression. Accordingly, the chip space base can have a chip space base profile that corresponds to the milling edge, i.e., follows the milling edge, a wave crest or a wave trough, a peak, a notch, a notch, and the like, or at least partially comprise such a structure.

[0043] The milling edge can, for example, be a continuous, in particular smooth, milling edge. However, the invention is also applicable to discontinuous milling edges, i.e., milling edges with roughing teeth and the like. For discontinuous milling edges, the envelope of the respective maximum milling edge radii can be used as the milling edge profile. Alternatively, the locally averaged milling edge radius can be used as the milling edge profile. In particular, the milling edge profile can be understood as the radial profile of the milling edge without taking into account any, e.g., local, fine structuring of the milling edge, such as roughing teeth, i.e., the radial profile of the coarse structure of the milling edge.

[0044] The phrase "following the milling edge profile" is to be understood in particular as meaning that the profile of the chip space base, except for discontinuous milling edge structures, in particular fine structuring such as roughing teeth, is essentially congruent with the milling edge profile. In particular, viewed in the longitudinal direction of the milling edge, the radial profile of the chip space base, i.e., the chip space base profile, can follow or correspond to the radial profile of the milling edge, i.e., the milling edge profile. Accordingly, as already mentioned, geometric shapes can be formed or formed in the chip space base corresponding to the milling edge and essentially congruently.

[0045] The chip space base can be defined, for example, by a substantially smooth surface or line, regardless of whether the milling edge is continuous or discontinuous. In particular, the phrase "following the milling edge profile" can be understood as "following the profile except for discontinuous fine structuring" or as "congruent except for discontinuous fine structuring." However, in cases where the milling edge has a discontinuous fine structuring, e.g., roughing teeth, the possibility of the chip space base having a structure corresponding to the fine structuring of the milling edge should not be ruled out.

[0046] The milling tool can therefore, for example, have a milling edge with a smooth structure (in particular also: a continuous structure) which, in the at least one milling edge section, has a milling edge profile with a non-linear progression, wherein the chip space base also has a smooth structure and follows the milling edge profile. Furthermore, it is possible for the milling edge to have a fine structure (in particular also: a discontinuous structure) and, in the at least one milling edge section, to have a milling edge profile with a non-linear progression, wherein the chip space base can have a continuous structure, in particular a smooth structure, or a discontinuous structure following the milling edge profile.

[0047] The at least one milling edge can have several of the aforementioned milling edge sections. For example, between 2 and 10, in particular between 2 and 5, milling edge sections can be present along the axial length of the machining head. Successive milling edge sections can be configured in their coarse structure as alternating wave crests and wave troughs, e.g., in the manner of a Christmas tree structure. It should be noted in particular at this point that the invention described herein is particularly suitable for so-called Christmas tree cutters, whose milling edge profile resembles a Christmas tree structure.

[0048] In embodiments, it can be provided that the milling tool, in particular a base body of the milling tool, has an overall pagoda-shaped profile, wherein milling edges formed on the pagoda-shaped profile can have chip spaces arranged upstream in the circumferential direction and as defined herein, in which the chip space base follows the milling edge profile. For example, the milling tool can be designed such that, in at least one, preferably in all milling edges, the respective milling edge profile and chip space base profile essentially correspond to one another, e.g., are congruent to one another, in particular in milling edge sections that include non-linear milling edge profile sections.

[0049] A milling edge section can comprise several subsections, which can be, for example, convexly or concavely curved with respect to the working axis of rotation, or can have a linear profile. In particular, several subsections with curved or linear profiles can be combined according to the desired milling profile.

[0050] The milling edge can have a predetermined helix or helical shape relative to the working axis of rotation, for example, at a predetermined, in particular constant, helix angle. However, in embodiments, the helix angle can also be provided to change along a milling edge, for example, varying according to a predetermined pattern.

[0051] The helix angle(s) of the milling edge(s) can be selected in particular in embodiments such that, when used properly in milling operation, in the respective working area in which the milling tool is in contact with the workpiece to be machined, at least one milling edge is always in engagement with the workpiece, at least in sections, for example a milling tooth.

[0052] The chip space can extend over a predetermined angle of rotation relative to the working axis of rotation, in particular one that remains constant along the chip space. In variants, the chip space can have a width measured in the circumferential direction relative to the working axis of rotation and essentially constant along the chip space. For example, the chip space can be designed as a groove upstream of the milling edge in the working direction of rotation. The chip space itself can have an essentially constant height along the chip space, following the profile of the milling profile, whereby the height of the chip space can be understood as the vertical or radial distance between the chip space base and the milling edge.

[0053] The chip space can have a first chip face extending between the milling edge and the chip space base, and furthermore at least one second chip face adjoining the chip space base and opposite the first chip face. The second chip face, like the first chip face, can follow the milling edge profile and have a substantially constant width, in particular a mean width, along the length of the milling edge.

[0054] The chip space can, for example, have a U-shaped or V-shaped shape in cross-section with respect to the longitudinal extent of the chip space, wherein a first leg can be formed between the milling edge and the chip space base or chip space root, corresponding, for example, to the first chip surface, and wherein a second, preferably shorter, leg, corresponding, for example, to the second chip surface, can adjoin the chip space base or chip space root.

[0055] With the proposed design of the chip space base, the chip space can be configured in particular such that, for example, the chip face associated with the milling edge, in particular the chip face adjoining the milling edges radially inward, or also other chip faces, each have a substantially constant width perpendicular to the milling edge or in the radial direction and / or in the circumferential direction along the chip space or the milling edge. In particular, in this way, substantially consistent chip formation and chip removal can be achieved across the entire milling edge, which can advantageously influence the milling result.

[0056] The proposed design, with a chip space whose chip space base follows the milling edge profile, has proven to be particularly smooth-running and / or low-vibration, allowing comparatively high surface qualities to be achieved, especially when milling workpieces. Furthermore, compared to state-of-the-art milling cutters that feature one or more of the above-mentioned milling edge sections but a chip space base that does not follow the milling edge profile, improved stability combined with a reduced risk of breakage, particularly in the area of ​​the milling edge, and generally increased service life can be achieved.

[0057] As already indicated, in embodiments, the proposed milling tool may be provided with at least one milling edge, preferably each of the milling edges, if multiple milling edges are present, comprising multiple milling edge sections as defined herein. The multiple milling edge sections may be arranged one behind the other along the respective milling edge, in particular directly behind one another.

[0058] At least one of the milling edge sections, optionally each of the milling edge sections, can be designed as a milling tooth, particularly dome-shaped with respect to the working axis of rotation. The aforementioned embodiments particularly enable the implementation of Christmas tree cutters with a Christmas tree-shaped milling profile.

[0059] The milling teeth can have rounded or tapered tooth tips, and rounded, tapered, and / or substantially straight tooth roots. For example, two adjacent milling teeth can be connected by a milling edge section with a straight edge profile. In particular, the milling teeth and milling roots, and associated chip spaces, as well as other sections of the milling tool in the region of the machining head, can be designed such that the machining head is shaped like a pagoda.

[0060] In embodiments, one or more milling edges, e.g., with a predetermined helix angle and a predetermined pitch angle, can extend on a pagoda-shaped base body, for example, such that a constant distance, measured in the radial direction or perpendicular to the milling edge, exists between the milling edge and the chip space base or chip space root along the milling edge. In particular, the chip face formed between the milling edge and the chip space root or chip space base can have a constant width measured perpendicular to the milling edge, i.e., the transverse extent, in particular the mean transverse extent, of the chip face can be essentially constant, following the course of the chip space.

[0061] In embodiments of the milling tool, at least one of the at least one milling edge, in particular the milling edge profile, can be formed on a milling lug extending transversely to the circumferential direction at least partially across the working area. The milling lug can have a predetermined width measured in the circumferential direction, which can, for example, be substantially constant along the milling edge. In particular, the milling lug can be formed as a web extending with a predetermined helix angle and with a predetermined, in particular constant, width in the circumferential direction.

[0062] In the milling lug or web, the radially outer edge located or oriented in the working direction of rotation can be designed, for example, as a milling edge, and the side surface of the web oriented in the working direction of rotation can be designed as a rake face. A radially outward-facing flank surface, which can be inclined at a predetermined flank angle, can adjoin the milling edge.

[0063] The web or milling lug can protrude radially from a base body of the milling tool by a predetermined, preferably substantially constant, radial height along the milling edge. The chip space base can be formed at least partially as a recess in the base body upstream of the milling lug in the working direction of rotation.

[0064] In embodiments, it can be provided that between the chip space base of a first milling lug and a flank edge of a flank of a second milling lug immediately following in the working direction of rotation, the base body has a base body segment that follows the milling edge profile of the first and / or second milling lug. A radially outward-facing surface of the base body segment can be at a higher level, measured radially with respect to the working axis of rotation, than the chip space base or the chip space root. The flank edge is understood to be the edge on a flank of the milling lug that is opposite the milling edge in the opposite direction of rotation to the working direction of rotation.

[0065] The level of the base body segment can be essentially constant between two milling lugs and / or can rise toward the flank edge of the second milling lug. By appropriately designing the base body segment downstream of the milling lug in terms of the working direction of rotation, the stability of the milling lug can be improved and, for example, the risk of breakage can be reduced.

[0066] By using or forming the aforementioned milling lugs with a predetermined width in the circumferential direction, it can also be ensured that sufficient material is available for resharpening the milling edge.

[0067] A further advantage of the proposed design of the milling edge, for example in the form of a milling groove with a defined width in the circumferential direction, can be seen in the fact that the shape of the milling edge, in particular the helix angle, and the shape of the chip space, in particular the chip face(s) and / or the chip root, can be freely selected within relatively broad limits and adapted to specific requirements. These adaptation options provide further options for improving the achievable milling accuracy, especially the surface quality, of the workpieces to be machined.

[0068] In embodiments, the milling edges can be designed such that the ratio between the number of milling edges arranged consecutively in the circumferential direction per revolution with respect to the working axis of rotation and the minimum profile diameter of the working area is between 0.2 and 1.0.

[0069] In further embodiments, several of the milling edge sections can be designed as milling teeth, in particular dome-shaped with respect to the working axis of rotation. The ratio between the number of milling teeth arranged consecutively in the circumferential direction per revolution with respect to the working axis of rotation and the minimum profile diameter of the working area of ​​the milling tool can be between 0.2 and 1.0 in embodiments. The milling teeth arranged consecutively in the circumferential direction can, for example, be arranged and configured to be substantially congruent with one another with respect to a predetermined axial position with respect to rotation about the working axis of rotation.

[0070] The minimum profile diameter is defined as the smallest milling diameter of the milling tool in the working area. The minimum profile diameter can be located anywhere along the milling edge profile.

[0071] With regard to the possible number of milling edges or milling teeth per revolution, the design of the chip spaces proposed here makes it possible, compared to the state of the art, to provide more milling edges or milling teeth per revolution with a similar milling cutter geometry without significantly impairing the stability of the milling tool, whereby in embodiments the stability can even be increased compared to milling cutters according to the state of the art despite the increased number of milling teeth.

[0072] The milling tools proposed herein are particularly suitable for machining workpieces made of metal and / or plastic. For example, milling cutters constructed according to the proposed design are suitable for use as finishing cutters, for example, for producing so-called Christmas tree structures on steam turbines and generator barrels, for attaching corresponding rotor blades. In particular, it has been shown that the milling tool proposed herein can produce Christmas tree structures with a comparatively high surface quality, while simultaneously achieving advantageous service life.

[0073] Compared to conventional milling tools whose chip space base is not designed according to the invention described herein, the milling tool proposed herein can, for example, double the tool life. Due to the essentially freely configurable shape of the milling lugs and / or the chip space, and / or the fact that milling lugs can be arranged with a comparatively small pitch angle, for example in the range between 8° and 120°, vibrations occurring during the milling process can be reduced by up to 1.5 times compared to conventional milling tools. It can be seen that the solution proposed herein enables comparatively high surface qualities while simultaneously providing advantageous tool life.

[0074] As already indicated, in embodiments of the milling tool, it can be provided that a flank extends on at least one of the at least one milling edge opposite to the working direction of rotation, i.e., with respect to the working axis of rotation in the circumferential direction opposite to the working direction of rotation of the milling tool. The flank can have a predetermined width measured in the circumferential direction, wherein the width, in particular the mean width, as already indicated, can be constant following the course of the milling edge.

[0075] In some embodiments, the flank surface can be inclined relative to the circumferential direction, for example, forming a flank angle in the range between 0° and 15°. The flank angle can be substantially constant along the milling edge.

[0076] By appropriately selecting the width of the flank, the mechanical stability of a particular milling lug and / or milling tooth can be adjusted. The width of the flank can be selected, for example, depending on the pitch, i.e., the pitch angle defined between adjacent milling edges.

[0077] In the milling tool, the pitch angle defined by the milling edges is three to 20 times, in particular three to five times, the circumferential angle assigned to the flank.

[0078] With the milling tool configuration proposed herein, it is possible to flexibly adjust the pitch angle of the milling edges and the circumferential angle of the flank, and / or the distribution of the milling edges in the circumferential direction, for example, such that during a milling operation, two or more milling edges are always in contact with the workpiece to be milled, at least in sections. In particular, this can improve the smooth running of the milling tool, and improvements in the achievable surface quality can be achieved by reducing vibrations.

[0079] In embodiments of the milling tool, as already indicated, it can be provided that a plurality of milling edges are formed in the circumferential direction with respect to the working axis of rotation. Milling edges that directly follow one another in the circumferential direction are preferably arranged rotationally symmetrically to one another with respect to the longitudinal direction of the working axis of rotation. In other words, at least two of the plurality of milling edges can be arranged and / or formed geometrically congruent to one another with respect to rotation about the working axis of rotation.

[0080] In certain embodiments, immediately consecutive milling edges can be arranged at a pitch angle in the range between 8° and 120° to one another.

[0081] As at least already indicated, at least one of the at least one milling edge can have a predetermined helix angle. Preferably, all milling edges have the same helix angle, or essentially the same helix angle profile in the longitudinal direction of the working rotation axis. The helix angle(s) can, for example, be in the range from 5° to 50°, preferably 20°. However, it is also possible for the helix angle to change along the milling edge, or for the helix angle to vary along the milling edge, for example, between a minimum and maximum helix angle.

[0082] In embodiments, it can be provided that the pitch angle(s) and helix angle(s), in particular the course of the pitch angle(s) and helix angle(s) along the working axis of rotation, are set up in such a way that at least one milling tool sector, in particular one spanned in the circumferential direction, is present, in which, viewed in axial projection with respect to the working axis of rotation, a first milling tooth of a first milling edge and a second milling tooth of a second milling edge are located, wherein the first milling edge is spaced apart from the second milling edge in the circumferential direction by at least 1 times the pitch angle, for example by an integer multiple of the pitch angle, and wherein the milling tool sector sweeps over a circumferential angle which is less than or equal to the pitch angle.In other words, the pitch angle(s) and helix angle, in particular the helix angle, can be selected such that, in an axial plan view of the milling tool, at least two milling teeth are located within a milling tool sector, for example, are located substantially one above the other in the axial direction, wherein the milling tool sector is defined with respect to the working axis of rotation and encloses an angle in the circumferential direction which is less than or equal to the pitch angle. The first and second milling teeth located in the same milling tool sector can, for example, be assigned to two milling edges which are spaced apart from one another in the circumferential direction by 1 times the pitch angle of the milling tool, in particular the minimum pitch angle of the milling tool. When forming corresponding milling tool sectors by appropriate adjustment orBy selecting the helix angle / pitch angle, it is possible to ensure that, during operation of the milling tool, at least in the respective milling tool segment, two milling teeth with different cutting edges engage the material being milled simultaneously. This can, for example, result in comparatively smooth operation, particularly with reduced vibration.

[0083] In embodiments, it can further be provided that the milling tool has a rake angle in the range of -3° to 24° for at least one, preferably for each, of the milling edges, and / or a wedge angle in the range of 51° to 93°. These angles are particularly suitable for the structure and design of the milling tool proposed herein, whereby advantageous running properties of the milling tool during milling can be achieved, in particular, by using the aforementioned angle ranges. The latter also applies to the clearance angle; for suitable angle ranges, reference is made to the above explanations.

[0084] In embodiments of the milling tool, as already described above, it can be provided that the at least one milling edge, preferably all of the milling edges, extend(s) over a predetermined axial length of the working area, measured parallel to the working axis of rotation, wherein the at least one, preferably all, milling edge(s) can have a milling edge profile which corresponds to a, in particular wave-shaped, fir tree profile, wherein the fir tree profile can comprise at least two, preferably at least three wave crests and / or wave troughs. The machining area of ​​the milling tool comprising the fir tree profile can, as mentioned, for example, have an overall shape designed in the manner of a pagoda.

[0085] In embodiments of the milling tool, the working area can, as already mentioned, comprise a base body. The base body can be designed such that the at least one milling edge is spaced radially from the base body, measured perpendicular to the milling edge, in particular protruding beyond the base body by a predetermined height measured perpendicular to the milling edge or radially to the working axis of rotation. The height, or a corresponding average height, can be substantially constant along the length of the milling edge, for example.

[0086] As already indicated, the base body can comprise one or more shoulder segments between immediately adjacent milling edges in the circumferential direction, the contour of which follows the milling edge profile. Each shoulder segment can extend, viewed in the circumferential direction of the working axis of rotation, between a milling edge and / or between the chip space base and / or chip space root associated with the milling edge and a flank edge upstream of the milling edge in the working direction of rotation. For the definition of the flank edge, please refer to the explanations above.

[0087] Such shoulder segments, which can be formed, for example, between the chip space of one milling edge and the flank of a milling edge positioned upstream in the working direction of rotation, make it possible to further improve the mechanical strength and thus the stability of the milling edges or milling studs. For example, the shoulder segments can have radially outward-facing back surfaces whose radial height lies at least partially, preferably completely, above the chip space floor or protrudes above the chip space floor. Thus, the shoulder segments can be designed as a type of mechanical reinforcement to enhance the mechanical stability of the milling edges / milling studs.

[0088] In embodiments, it can be provided that with respect to at least one axial position along the working axis of rotation, ie with respect to at least one axial position, in the circumferential direction of the working axis of rotation, several successive, in particular rotationally symmetrically overlapping, milling edge sections, for example successive milling edges, are formed.

[0089] The base body, in particular each of the shoulder segments, can have one or more elevations and / or flat sections running parallel to the circumferential direction, for example dome-shaped in cross-section, between milling edge sections adjacent in the circumferential direction. Viewed in the radial direction with respect to the working axis of rotation or perpendicular to the milling edge, it can be provided in such embodiments in particular that the chip space base is at the same or at least partially at a lower level than a radial outer surface of at least one of the segments. In embodiments it can be provided that a respective chip space base or a respective chip space root and a shoulder segment immediately following in the working direction of rotation, for example an elevation, are at different levels, wherein the chip space base or the chip space root can be lower than the respective shoulder segment.In particular, this allows a milling edge section downstream of the respective shoulder segment in the working direction of rotation to be stabilized.

[0090] In embodiments, as already indicated, it can be provided that the milling tool comprises a base body, wherein the base body can have a plurality of coolant and / or lubricant outlet openings. The coolant and / or lubricant outlet openings can, for example, be oriented radially to the working axis of rotation. Furthermore, it is possible for the outlet openings to be arranged at least partially or in sections between the respective milling edge and / or respective chip space and a flank edge arranged upstream of the milling edge or chip space in the working direction of rotation. In embodiments, it can be provided that the opening planes of the outlet openings, viewed radially to the working axis of rotation, are at the same height as, or at least partially higher than, the respectively associated chip space base or chip space root. For example, the outlet openings can be arranged in the region of the above-mentioned segments of the base body.The outlet opening planes can, provided that the segments of the base body follow the milling edge profile, be oriented at least partially approximately perpendicular to the milling edge profile, so that, for example, an optimized supply of coolant and / or lubricant is possible.

[0091] Furthermore, in embodiments, it is possible for the cooling and / or lubricant outlet openings to be located within the shoulder segments, with at least two of the cooling and / or lubricant outlet openings being arranged at radially different heights. The radial heights of the cooling and / or lubricant outlet openings can vary and, in particular, can follow the milling edge contour. In particular, a distance measured perpendicular to the respective milling edge between a circular line running through the opening center of a cooling and / or lubricant outlet opening and the milling edge can be substantially the same for several, in particular all, cooling and / or lubricant outlet openings.In other words, the proposed milling tool can achieve that the distance, measured for example perpendicular to the milling cutter surface, between cooling and / or lubricant outlet openings and a respective milling edge is substantially the same for at least the cooling and / or lubricant outlet openings assigned to a milling edge, or for all cooling and / or lubricant outlet openings, whereby, for example, an improved distribution of cooling and / or lubricants can be achieved.

[0092] With the milling tool design proposed herein, it is possible to freely position the exit openings between adjacent milling edges in the working direction of rotation or circumferential direction in a suitable manner and within certain limits. In particular, the exit openings can be arranged, for example, at least partially or in sections outside the chip space base, so that, for example, temporary blockage of the exit openings by chip material can be avoided during milling.

[0093] In particular, it is clear from the above statements that the object underlying the invention can be achieved with the milling tool proposed here. In particular, improved service life and / or improved surface qualities can be achieved.

[0094] In embodiments of the invention, a manufacturing method for a milling tool, i.e. a method for manufacturing a milling tool, is provided, wherein the milling tool has at least one milling edge and a chip space associated with the milling edge, wherein the milling edge has a milling edge profile with a sectionally non-linear course, comprising the following steps: - Providing a milling tool blank; - producing at least one milling edge and the associated chip space on the milling blank by material removal, whereby - the material removal is carried out in such a way that, in the finished milling tool, a radial or vertical distance between the milling edge and the chip space base is essentially constant, at least in sections.

[0095] In some embodiments, a milling process may be used for material processing. For example, the working area, including the milling edge(s) and the spacing area(s), may be produced using a milling process.

[0096] The material removal can be carried out in embodiments such that each of the milling edges is formed on a milling lug projecting above a base body, and the contour of the base body between circumferentially adjacent milling lugs is formed by material removal corresponding to the milling edge contour, ie that the contour of the base body between circumferentially adjacent milling lugs is produced by material removal in such a way that the base body has a contour corresponding to the milling edge contour, in particular that the contour of the base body follows the milling edge contour.

[0097] Materials such as solid carbide (SHM) or high-speed steel (HSS) are particularly suitable for manufacturing the milling tool. In particular, the milling tool can be a single-piece milling tool made from a single material.

[0098] The invention will be explained in more detail below, particularly with regard to further features and advantages, based on the description of exemplary embodiments of a milling tool and with reference to the accompanying drawings. Fig. 1 a side view of the milling tool of a first variant; Fig. 2 a cross-sectional view of the milling tool; Fig. 3 a detailed view of the machining head of the milling tool according to Fig. 1; Fig. 4 a diagram with milling edge profile and chip space base profile; Fig. 5 schematically shows a section of an axial section of the machining head of the milling tool; Fig. 6 a milling tool according to a second variant; Fig. 7 a milling tool according to a third variant; Fig. 8 to 10 cutouts of different milling edge profiles; Fig. 11 a schematic side view of the milling tool of the Fig. 6; Fig. 12 an axial plan view of the milling tool according to Fig. 11; and Fig. 13 a side view of the milling tool according to Fig. 12.

[0099] Corresponding parts and components in Fig. 1 to Fig. 13 are provided with corresponding reference numerals.

[0100] Fig. Figure 1 shows a milling tool 1 according to a first variant. The milling tool 1 of the illustrated embodiment is an end mill, in particular a finishing mill, with a fir-tree-shaped milling edge profile or milling profile. Milling cutters of this type are also known as fir-tree cutters.

[0101] Although the following description relates to a Christmas tree cutter, the features and properties described below, in particular regarding the milling edge(s) and / or chip space(s), are not limited to Christmas tree cutters, but can also be applied and implemented with other cutter types.

[0102] The milling tool 1 comprises a shaft 2 and a machining head 3 connected thereto. The shaft 2 is designed to clamp the milling tool 1 in a chip chuck (not shown).

[0103] For milling, for example for finishing, a workpiece (not shown), the clamped milling tool 1 is rotated by means of a drive coupled to the chuck about the working rotation axis 4 (in particular also: tool axis), which in this case coincides with the longitudinal axis of the milling tool 1, and the machining head is moved relative to the workpiece to produce the respectively desired milling structure, for example in engagement with the workpiece.

[0104] The machining head 3 of the milling tool 1, i.e. the working area of ​​the milling tool, comprises a plurality of milling edges 5 running transversely to the circumferential direction U or the working direction R in the circumferential direction U with respect to the working axis of rotation 4, or in the working direction R with respect to the working axis of rotation 4.

[0105] The milling edges 5 are, as can be seen Fig. 2, which shows a cross-sectional view of the milling tool 1, are arranged successively in the working direction of rotation R at a predetermined pitch angle T rotationally symmetrical to the working axis of rotation 4. In the present case, the pitch angle T is approximately 60 degrees, although, as will be apparent from the further description, other, in particular smaller, pitch angles T are also possible.

[0106] As from Fig. 1 and the detailed representation of the Fig. 3, the milling edges 5 run on a base body 6, in particular viewed in radial projection onto the base body 6 or in radial projection onto the lateral surface of the base body 6, at a predetermined helix angle.

[0107] The helix angle and / or the above-mentioned pitch angle T is / are preferably selected such that a milling operation of a workpiece can be carried out in such a way that at least two milling edge sections of two different milling edges 5, which are successive in the circumferential direction, are always in engagement with the workpiece, which in connection with Fig. 9 and Fig. 10 will be described in more detail. Such an arrangement of the milling edges 5 on the base body 6 is made possible by the design of the milling tool proposed herein, wherein engagement of two milling edges 5 enables milling with improved running smoothness, whereby improved milling results, e.g., surface qualities, can be achieved on the workpiece to be machined.

[0108] The milling edges 5 of the milling tool 1 each have at least one, in the present case several, milling edge sections 5.1 - 5.4, in which a milling edge radius F ( Fig. 2) defined milling edge profile P ( Fig. 4) has at least one section with a non-linear profile. The milling edge radius F is understood, particularly in the case of straight, i.e., continuous, milling edges 5 as in the illustrated embodiment, to be the respective radial distance of the milling edge 5 from the working rotation axis 4 or tool axis.

[0109] At least one of the milling edge sections 5.1 - 5.4 can be designed such that, for example, the local or locally averaged milling edge radius F initially increases along the milling edge 5 and then decreases again, which is the case, for example, with the milling teeth 19 present in the milling edge sections 5.1, 5.3, and 5.4 shown, which each have a rising 20.1 and a falling milling edge flank 20.2 in the direction from the shaft 2 to the working area 3.

[0110] Particularly in the area of ​​the tooth apex, the milling edges have 5 sections with a non-linear profile. The milling edges 5 of the Fig. 1 contain a mixture of sections with linear and non-linear progression, whereby designs without linear milling edges are also possible, similar to, for example, in Fig. 6 or Fig. 7.

[0111] At least one of the milling edge sections 5.1 - 5.4 can be designed such that in at least one milling edge section, the milling edge profile P, ie the curve of the milling edge profile P, geometrically considered, has an inflection point (e.g. between 5.1 and 5.2), an extreme point (at 5.1, 5.3, 5.4, at the vertices of the milling teeth 19) and / or a discontinuity point in its derivative or gradient (e.g. at 5.2, in the transition area between the linear section and the rising milling edge flank 20.1).

[0112] The respective milling edge section can have one or more, e.g., substantially linear or substantially rectilinear, subsections with different gradients. Further profiles for the milling edge profile P are conceivable, whereby, apart from the milling edge profiles shown in the figures relating to the milling tool 1, the underlying invention can also be applied to other milling edge profiles P that exhibit a profile with at least one non-linear section.

[0113] Fig. 4 shows an example of a milling edge profile P, the shape of which is based on the Fig. 1 to Fig. 3 shown milling tool 1 is selected. In the illustration of the Fig. 4, the axial length L is plotted on the abscissa axis, measured for example from the front axial end of the machining head 3 in the direction of the shaft 2, and the milling edge radius F, or the radius of the milling edge base discussed below, hereinafter referred to as milling edge base radius G, is plotted on the ordinate axis.

[0114] As well as from Fig. 4, the milling edge profile P comprises several milling edge sections 5.1 - 5.4 in which the milling edges 5 show a non-linear course at least in sections.

[0115] To avoid any ambiguities, it should be mentioned that the milling edge radius F can be understood here in particular as the local distance, measured in the radial direction, between the radially outer edge of the milling edge and the working rotation axis 4.

[0116] In the milling tool 1 shown in the figures, the base body 6, as well as the machining head 3, have a shape similar to a pagoda. Accordingly, the milling edge sections can be designed, for example, as wave crests, e.g., in 5.1, 5.3, and 5.4, or wave troughs, e.g., in 5.2, with a linear or curved milling edge profile. In the present example, the wave crests are designed as milling teeth 19.

[0117] The milling edge 5 shown in the figures is a smooth, i.e., continuous, milling edge, in particular without roughing teeth and the like. However, in connection with the invention, it is pointed out that the invention described herein is also applicable to discontinuous milling edges, for example, roughing teeth and the like. In the case of a discontinuous milling edge, a locally averaged milling edge radius or a locally smoothed milling edge radius can be considered, for example. For further discussion regarding discontinuous milling edges, reference is made to the statements above.

[0118] The at least one milling edge section can, for example, have a milling edge profile P in which the milling radius F can vary by up to 0.5 times the maximum milling edge radius of the respective milling edge.

[0119] Across the axial length of the machining head 3, for example, between two and ten of the milling edge sections 5.1 - 5.4 can be present along a milling edge 5, for example in the form of several milling teeth 5.1, 5.3, 5.4 with intermediate tooth roots, e.g., at 5.2. For example, the milling profile can be designed in the manner of a Christmas tree milling profile, wherein the machining head 3, in particular the base body 6, can have a pagoda-like shape, as shown in the exemplary embodiments of the figures.

[0120] The at least one milling edge 5 can have several of the aforementioned milling edge sections, which can, for example, be convexly or concavely curved radially with respect to the working rotation axis 4. Further curvatures can, for example, result from a more or less twisted profile of the milling edges 5 themselves. However, the milling edge sections can, at least in sections, have a linear profile. It should be noted that each of the milling edges 5 can also be regarded as a milling edge section, since each of the milling edges comprises at least one non-linear section.

[0121] In the machining head 3, chip spaces 7 are arranged upstream of the milling edges 5 in the working direction of rotation R, through which the chip material created during the milling process during the cutting engagement of the milling edges 5 or lifted from the workpiece can be received, guided, shaped and / or transported.

[0122] The relative arrangement of milling edge 5 and chip space 7 is shown in Fig. 5 shows a sectional view relating to a section of an axial section of the milling tool 1 as an example.

[0123] As in Fig. 5, the chip space 7 is defined in the present case, among other things, by a chip surface 8 located radially inside the milling edge 5 and adjoining the milling edge 5, i.e. a chip surface 8 adjoining the milling edge and extending in the radial direction towards the working axis of rotation 4, which chip surface 8 extends to the chip space base 9 of the chip space 7. The intersection point or the intersection line 10 between the chip space base 9 and the chip surface 8, or the contour line 10' running in the chip space base 9 at which the chip space base 9 has the smallest radial height relative to the working axis of rotation 4, can also be referred to as the chip space root. Furthermore, the chip space 7 is defined by a width measured in the circumferential direction U or in the working direction of rotation R, or by a circumferential angle measured with respect to the working axis of rotation 4, which can be essentially constant, for example, along the milling edge 5.In particular, the chip space 7 can have a cross-section in sections perpendicular to the milling edge 5 that is substantially constant along the milling edge 5. In alternative embodiments, it is possible for the cross-section of the chip space 7 to vary along the milling edge 5, whereby the width and / or height of the chip space can vary.

[0124] As from Fig. 1 and Fig. 2, the chip space base 9 or the chip space root 10 or 10' along the milling edge 5 has a course that follows the milling edge profile P. This is shown in the diagram of the Fig. 4 is shown as an example, where the dashed line represents the profile of the chip space base 9 corresponding to the profile of the milling edge 5, or alternatively the profile of the chip space root 10, 10', the chip space base profile S. As already indicated, the chip space base profile S is defined by the radius G of the chip space base 9 or the chip space root 10, 10' measured with respect to the working axis of rotation. Fig. 4 shows the radius G of the chip space base as a function of the axial length L.

[0125] The wording "following the milling edge 5" is to be understood in particular to mean that the distance between the chip space base 9 or chip space root 10, 10' and the milling edge 5 measured perpendicular to the milling edge 5 or measured in the radial direction with respect to the working rotation axis 4 is at least partially substantially constant or constant. In the representation of the Fig. 4, the chip space base 9 or the chip space base profile S follows the milling edge profile P over the entire length of the machining head 3, both in linear and non-linear sections of the milling edge profile P. However, it is also possible that the chip space base profile S only partially follows the milling edge profile P in the sections with a non-linear course, e.g. in the non-linear sections it only runs parallel to the milling edge 5 in sections.

[0126] The respective chip spaces 7 can, as in the illustrated embodiments, have a height H that is substantially constant along the milling edge 5, wherein the height H of the chip space 7 can be determined, for example, by the difference between the milling edge radius F and the respective radius G of the chip space base 9, or by the vertical distance of the chip space base 9 from the milling edge. Depending on the design of the chip space 7, the height H of the chip space 7 can be identical to the width of the chip face 8.

[0127] With the shape of the chip spaces 7 designed as described, a chip face 8 can be obtained which has a substantially constant width B across the course of the milling edge 5, but at least in the milling edge sections 5.1 - 5.4, measured, for example, as the distance between the chip space base 9 and the milling edge 5 measured perpendicular to the milling edge 5. The chip face 8 can, for example, be designed in the form of a chip face band with a substantially constant width measured perpendicular to the milling edge.

[0128] By means of a constant width B of the chip surfaces 8 and / or a constant height H of the chip spaces 7, at least similar, in particular substantially constant, chip forming properties and / or a similar and / or substantially constant chip removal can be achieved, for example, over the entire length of the milling edge 5, whereby improved surface qualities can be achieved during milling.

[0129] Furthermore, by having the chip space base 9 or the chip space root 10, 10' follow the milling edge profile P, improved stability of the milling edge 5 and the milling tool 1, in particular of the machining head 3, can be achieved compared to prior art designs. Improved stability can, for example, reduce the risk of breakage, particularly in the area of ​​the milling edges 5, thereby enabling extended tool life.

[0130] In particular, improved mechanical stability can be achieved for the milling teeth 19, because mechanical stabilization and support of the milling teeth 19 can be achieved by the saddle-like projections 21 formed in the circumferential direction U between adjacent milling teeth 19, the contour of which, e.g. in sections parallel to the working rotation axis 4, follows the contour of the milling teeth or corresponds to the contour of the milling teeth.

[0131] With the proposed geometry of the chip spaces 7, compared to known milling tools in which the chip space base extends between adjacent milling teeth 19, for example, at a constant radial height above the working axis of rotation, a modified mass distribution can be achieved in the milling tool, for example with an increased moment of inertia, which can possibly influence the smooth running of the milling tool, in particular can improve it.

[0132] The information related to Fig. 1 to Fig. The chip spaces 7 described in Figure 5 are essentially U-shaped or V-shaped in the area immediately adjacent to the milling edge 7, with a first leg 11 running between the chip space base 9 and the milling edge 7, which is essentially formed by the chip surface 8, and a second leg 12. The second leg 12 has a smaller radial height than the first leg 11 and extends between the chip space base 9 and a transition region 13, which in the present embodiment is designed in the manner of a plateau or a shoulder segment. The transition region 13 or the corresponding shoulder segment is raised relative to the chip space base 9 and extends from the second leg 12 in the working direction of rotation R to a flank edge 14 of a milling edge 5 following in the working direction of rotation R.

[0133] The transition region 13, or the shoulder segment 13, can, however, be designed differently in certain embodiments. For example, it is possible for the transition region 13 to rise continuously from the chip space base 9, e.g. without explicitly forming a shoulder, towards the flank edge 14, wherein the transition region 13 can optionally be concave or convex, in particular substantially uniformly convex or concave, curved, which in Fig. 5 is shown as the first variant 13.1 according to the dashed-dotted line.

[0134] Furthermore, it is possible that the transition area 13 extends from the chip space base 9 at an approximately constant radial height in the circumferential direction U, or working direction of rotation R, and in the area of ​​the flank edge 14 shows a substantially radial course, which in Fig. 5 is shown as the second variant 13.2 according to the dash-double-dotted line.

[0135] Adjacent to each of the milling edges 5, opposite to the working direction of rotation R, is a flank 15 which is bounded in the circumferential direction U by the flank edge 14 on the one hand and the milling edge 7 on the other. Measured in the circumferential direction U, the flank 15 has a predetermined flank width E which, either measured as an absolute length in the circumferential direction or measured as an angle with respect to, for example, the working axis of rotation 4, is essentially constant or consistent along the milling edge 7.

[0136] In the exemplary embodiment shown, the respective milling edges 7 and flanks 15 form a lug or milling lug running along the milling edge 7, which has the predetermined flank width E measured in the circumferential direction U, runs at a predetermined helix angle on the base body 6, and has a predetermined, in particular essentially constant, thickness measured from the base body 6 in the radial direction. Measured with respect to the working rotation axis 4, the radial height of the milling lug varies according to the milling edge profile P, so that the milling teeth 19 are formed in the region of the milling edge sections 5.1, 5.3, and 5.4. The difference between the radial height of the milling lug and the radius G of the chip space base 9 can, in embodiments, be essentially constant following the course of the milling edge 5. In further embodiments, it can be provided that the height of the milling lug above the chip space base, measured perpendicular to the milling edge, is essentially constant.With constant heights, improved stability, especially fracture stability, can be achieved over the longitudinal extent of the milling tunnel.

[0137] In the milling tools shown in the figures, the base body 6 is designed in the intermediate region between two milling edges 5 which follow one another in the circumferential direction in such a way that its contour follows the milling edge profile P, wherein the radial height of the base body measured with respect to the working axis of rotation 4 in the region between the chip space 7 of a first milling stud and the flank edge 14 of a subsequent second milling stud can be greater than the radius G in the chip space base 9. The flank 15 and the flank edge 14 are also designed in such a way, in particular in all milling studs, that they have a contour or a profile which follows the milling edge profile P, ie is geometrically congruent to the milling edge profile P.

[0138] With the proposed milling cutter geometry, a milling operation with improved running smoothness of the milling tool 1 can be achieved, and the generation of milling-related vibrations can at least be counteracted.

[0139] The free surface 15 can be designed such that it is inclined at a predetermined free surface angle W1, which can, for example, be in the range between 0° and 15°.

[0140] As from Fig. 1 and Fig. 3, the chip space 7 can be designed in particular such that its cross-section is constant over the entire length of the milling edge 5 or the chip space base 9, following the course of the milling edge 5 or the chip space base 9, but at least over the entire length of a milling edge section. For example, the chip space 7 can be designed as a type of groove which has a substantially constant geometry along the course along the chip space 7 in the radial direction and circumferential direction U. Corresponding structures can, for example, be produced in a corresponding blank by material removal, for example by milling.

[0141] Compared to conventional milling tools, in which the profile of the chip space base merely has a linear progression, the milling tool 1 proposed here makes it possible to increase the number of milling edges 5 or milling teeth 19 or milling lobes present in the direction of rotation U, i.e. it is possible to reduce the pitch angle T compared to known milling cutters. By reducing the pitch angle T, the milling tool 1 proposed here, in contrast to the known milling tools mentioned, can achieve an improvement in terms of the mechanical stability of the working area, since in the milling tools 1 proposed here, for example, the transition areas 13, in particular the saddle-like projections 21, have a stabilizing effect, so that in particular the risk of breakage can be reduced. By reducing the pitch T, i.e. increasing the number of milling lobes orMilling webs in the circumferential direction U, the service life can be increased by a factor of up to 1.5 compared to conventional milling tools.

[0142] In the milling tools 1 proposed herein, the chip space 7 and helix angle can be freely varied within wide limits without significantly changing or deteriorating the mechanical stability of the milling tool 1.

[0143] The milling lugs can be designed such that they have a wedge angle W2 in the range of 51° and 93°, and / or a rake angle W3 in the range of -3° and 24°.

[0144] In particular, due to the higher mechanical stability and strength of the milling lugs achievable with the advantageous milling cutter geometry proposed herein, the flank angle W1, wedge angle W2, and rake angle W3 can be selected comparatively flexibly, so that it is possible to flexibly adapt the milling tool 1 to the material to be machined in each case and / or in accordance with the milling edge profile P required in each case.

[0145] As is particularly evident from Fig. 1 and Fig. 3, the milling tool 1 further comprises a plurality of coolant and / or lubricant outlet openings 16. The coolant and / or lubricant outlet openings 16, hereinafter referred to as outlet openings 16 for short, can be designed, for example, as mouth openings of radial bores, which can be fluidically connected at the ends facing away from the outlet openings 16 to an axial coolant and / or lubricant channel extending inside the milling tool 1.

[0146] Due to the space-saving design of the chip spaces 7 in the circumferential direction U made possible by the present invention, the outlet openings 16 can be arranged comparatively flexibly compared to conventional milling tools. In particular, the outlet openings 16 can be arranged at least partially in the transition regions 13.

[0147] Since the contour of the transition regions 13 can follow the milling edge profile P, ie can be designed corresponding to the milling edge profile, the outlet openings 16 can be brought close to the milling edges 5 in terms of radial height, for example, so that coolant and / or lubricant distribution at the milling edges 5 can be improved.

[0148] Fig. 6 shows a milling tool 1' according to a second variant, and Fig. 7 shows a milling tool 1" according to a third variant.

[0149] The milling tools 1' and 1" according to the first and second variants differ from the milling tool 1 according to the first variant in particular in that the milling edges 5 are arranged at a different, in particular smaller, pitch angle T to each other. This shows that the milling edges 5 can be arranged comparatively flexibly in the milling tool proposed here. Furthermore, it is evident that the helix angle can be freely selected within wide limits.

[0150] Furthermore, it can be seen that different milling edge profiles P can be implemented with the proposed milling cutter geometry. Thus, the milling tool 1' according to the second variant has milling edges 5 with two wave valleys, while the milling tool 1" according to the third variant has at least three wave valleys in the milling edge profile P.

[0151] Out of Fig. 6 and Fig. 7 follows in conjunction with Fig. 1 to Fig. 5 further shows that with the milling cutter geometry proposed herein, the milling edges 5 can be arranged such that during the milling process at least two milling edges 5 are always in engagement with the workpiece, at least in sections, whereby the smooth running of the milling tool 1, 1', 1" can be improved.

[0152] Fig. 8 to Fig. 10 show sections of milling edge profiles P and associated chip space base profiles S, which can be implemented according to the invention proposed herein, and in which, in a region which comprises a non-linear course in the milling edge profile P, the chip space base profile S follows the milling edge profile P, or in which the chip space base profile S is designed to correspond, in particular geometrically congruent, to the milling edge profile P. For example, the chip space base profile S can be substantially displaced parallel to the milling edge profile P. It is also possible for the radial distance or the distance measured perpendicular to the milling edge 5 between the milling edge 5 and the chip space base 9 to be substantially constant or consistent over the course of the milling edge 5.

[0153] The Fig. 8 to Fig. 10 milling edge profiles P shown for corresponding milling edge sections show areas with an overall non-linear progression.

[0154] The Fig. The milling edge profile P shown in Figure 8 comprises two straight sections, wherein the milling edge radius F is essentially constant in a first section, and the milling edge radius increases linearly in a second section, so that the milling edge profile formed from both sections has an overall non-linear profile. At the intersection point 17 of the two sections, the derivative or gradient of the milling edge profile P has a point of discontinuity from a geometric perspective.

[0155] In the example of Fig. 9, the milling edge profile P, and correspondingly the chip space base profile S, exhibit a wave-like, non-linear profile with a wave trough and a wave crest. From a geometric perspective, the milling edge profile P exhibits an inflection point 18 in the area between the wave crest and the wave trough.

[0156] In the example of Fig. 10, the milling edge section shown is designed in the manner of a notch, in particular in the manner of a milling tooth 19, with two linear sub-regions, i.e. a linearly rising sub-region or a rising milling tooth flank 20.1, and a linearly falling sub-region or a linearly falling milling tooth flank 20.2, wherein the milling edge profile P has a discontinuity in its derivation at the intersection point 17 or apex of the two sub-regions. The milling edge section shown thus has an overall non-linear profile, wherein, according to the underlying invention, the chip space base profile S has a profile corresponding to the milling edge profile, i.e., likewise has a discontinuity in its derivation.

[0157] The milling edge sections shown in the figures can also have other profiles. For example, instead of a straight profile, a convex or concave curved profile of the milling edge can be provided, and any combination of milling edge sections mentioned and described herein in connection with the invention can be provided, in particular any combination of straight and curved sections with a constant, decreasing, or increasing milling edge radius, with increasing or decreasing pitch, etc.

[0158] Fig. 11 shows a schematic side view of a milling tool 1 according to Fig. 6, and Fig. 12 and Fig. 13 show an axial plan view and a side view of the milling tool 1.

[0159] In the schematic side view after Fig. 11, a minimum profile diameter D of the machining head 3 is marked, which at a predetermined point along the axial direction of the machining head 3, in the example of Fig. 11 located in the area of ​​the axial end of the machining head 3, is defined by the milling cutter geometry.

[0160] As in Fig. 11, at least one of the milling edge sections can be designed as a milling tooth 19, which is in particular dome-shaped with respect to the working rotation axis 4. The ratio between the number of milling teeth 19 arranged successively in the circumferential direction per revolution with respect to the working rotation axis 4 and the minimum profile diameter D of the working area 3 can, for example, be between 0.2 and 1.0. The milling tools 1 proposed herein can, as in Fig. 12 and Fig. 13, be designed in such a way that the pitch angle(s) T and the helix angle(s), or their course, is selected in such a way that at least one milling tool sector 22 is present, in which, viewed in axial projection with respect to the working rotation axis 4 (see Fig. 12) a first milling tooth 23 of a first milling edge 24 and a second milling tooth 25 of a second milling edge 26 are located, wherein the first milling edge 24 is spaced apart in the circumferential direction U by at least 1 times the pitch angle T from the second milling edge 26, and wherein the milling tool sector 22 sweeps over a circumferential angle which is less than or equal to the pitch angle T. In the example of Fig. 12, the milling tool sector 22 corresponds to the pitch angle T, whereby in embodiments the milling tool sector 22 can be smaller than the pitch angle T. For example, the milling tool sector can be 1 / 3 to 1 / 2 of the pitch angle.

[0161] Overall, it can be seen that with the milling tool proposed here and the proposed manufacturing method, a milling tool can be provided with which improved mechanical strengths, comparatively high surface qualities and improved service life can be achieved. List of reference symbols 1 milling tool 2 shaft 3 processing head 4 Working rotation axis 5 milling edge 5.1 - 5.4 Milling edge section 6 basic bodies 7 chip space 8 chip surface 9 Chip space base 10 Cutting line 10' contour line 11 first leg 12 second leg 13 Transition area 13.1 Transition area, first variant 13.2 Transition area, second variant 14 Free space edge 15 open space 16 Exit opening 17 Intersection 18 Turning point 19 milling teeth 20 milling edge flanks 21 saddle-like projection 22 Milling tool sector 23 first milling tooth 24 first milling edge 25 second milling tooth 26 second milling edge U circumferential direction R Working direction of rotation F Milling edge radius T pitch angle P milling edge profile L axial length G Radius chip space base H Height B Width S chip space basic profile E Open space width D minimum profile diameter W1 flank angle W2 wedge angle W3 rake angle

Claims

[1] Milling tool (1) designed as an end mill or finishing mill, which is made in one piece from a uniform material, preferably a Christmas tree milling cutter (1, 1', 1") or bore milling cutter, with a working area (3) which is rotatable about a working axis of rotation (4) for milling a workpiece and which has at least one milling edge (5) running transversely to the circumferential direction (U) of the working axis of rotation (4), wherein at least one of the at least one milling edge (5) comprises at least one milling edge section (5.1 - 5.4) in which a milling edge profile (P) defined by the radial distance (F) of the milling edge (5) from the working axis of rotation (4) along the milling edge (5) has a non-linear profile, wherein the milling edge (5) in the milling edge section (5.1 - 5.4) has a Chip space (7) is assigned, which is in the milling edge section (5.1 - 5-4) with a non-linear milling edge profile (P) has a chip space base (9, 10, 10') which at least partially follows the milling edge profile (P), wherein a flank (15) extends on at least one of the at least one milling edge (5) opposite to the working direction of rotation (R) of the milling tool (1), and wherein a pitch angle (T) defined by the milling edges (5) is three to 20 times the circumferential angle assigned to the flank (15). [2] Milling tool (1) according to claim 1, wherein a radial distance (H, B) or a distance measured perpendicular to the milling edge (5) between the milling edge (5) and the chip space base (9, 10, 10') along the milling edge (5) at least within the milling edge section (5.1 - 5.4) is substantially constant, in particular such that a chip surface (8) formed between the chip space base (9, 10, 10') and the milling edge (5) in the milling edge section (5.1 - 5.4) has a substantially constant width in the course along the milling edge (5). [3] Milling tool (1) according to claim 1 or 2, wherein at least one milling edge (5), preferably each milling edge (5), comprises a plurality of milling edge sections (5.1 - 5.4), and the plurality of milling edge sections (5.1 - 5.4) are arranged one behind the other, in particular directly behind the other, along the respective milling edge (5), and / or wherein at least one of the at least one milling edge (5), in particular milling edge profile (P), is formed on a milling lug extending transversely to the circumferential direction (U) at least partially over the working area (3), wherein the milling lug has a predetermined width (E) measured in the circumferential direction (U), which is substantially constant along the milling edge (5). [4] Milling tool (1) according to one of claims 1 to 3, wherein the ratio between the number of milling edges (5) arranged successively in the circumferential direction (U) with respect to the working axis of rotation (4) per revolution and the minimum profile diameter (D) of the working area (3) is between 0.2 and 1.0, wherein optionally several of the milling edge sections (5.1 - 5.4) are designed as milling teeth (5.1, 5.3, 5.4, 19) which are in particular dome-shaped with respect to the working axis of rotation (4), and wherein the ratio between the number of milling teeth (5.1, 5.3, 5.4, 19) arranged successively in the circumferential direction (U) with respect to the working axis of rotation (4) per revolution and the minimum profile diameter (D) of the working area (3) is between 0.2 and 1.

0. [5] Milling tool (1) according to one of claims 1 to 4, wherein the flank (15) has a predetermined width (E) in the circumferential direction (U), which is in particular constant in the course along the milling edge (5), wherein optionally the flank (15) is inclined with respect to the circumferential direction (U) to form a predetermined flank angle (W1) which is in particular substantially constant in the course along the milling edge (5), wherein the flank angle (W1) is preferably in the range between 0° and 15°. [6] Milling tool (1) according to one of claims 1 to 5, wherein a plurality of milling edges (5) are formed in the circumferential direction (U) with respect to the working axis of rotation (4), and directly successive milling edges (5) are arranged in the circumferential direction (U) at a pitch angle (T) in the range between 8° and 120°, and / or wherein at least two of the plurality of milling edges (5) are geometrically congruent to one another with respect to a rotation about the working axis of rotation (4). [7] Milling tool (1) according to one of claims 1 to 6, wherein at least one of the at least one milling edge (5), preferably all milling edges (5), has / have a helix angle in the range of 5° to 50°, preferably 20°. [8] Milling tool (1) according to claims 4, 6 and 7, wherein the pitch angle(s) (T) and helix angle(s) are arranged such that at least one milling tool sector (22) is present, in which, viewed in axial projection with respect to the working rotational axis (4), a first milling tooth (23) of a first milling edge (24) and a second milling tooth (25) of a second milling edge (26) are located, wherein the first milling edge (24) is spaced apart from the second milling edge in the circumferential direction (U) by at least 1 times the pitch angle (T), and wherein the milling tool sector (22) sweeps over a circumferential angle which is less than or equal to the pitch angle (T). [9] Milling tool (1) according to one of claims 1 to 8, wherein the milling tool (1) has for at least one, preferably for each of the milling edges (5), a rake angle (W3) in the range of -3° and 24°, and / or a wedge angle (W2) in the range of 51° and 93°. [10] Milling tool (1) according to one of claims 1 to 9, wherein the at least one milling edge (5), preferably all of the milling edges (5), has / have a milling edge profile (P) which extends / extends in and parallel to the working axis of rotation over a predetermined axial length of the working area (3), wherein the at least one, preferably all, milling edge(s) (5) have / have a milling edge profile (P) which corresponds to a, in particular wave-shaped, fir tree profile, wherein the fir tree profile comprises at least two, preferably at least three wave crests (5.1, 5.3, 5.4) and / or wave troughs (5.2). [11] Milling tool (1) according to one of claims 1 to 10, wherein the working area (3) has a base body (3) from which the at least one milling edge (5) is spaced apart, measured radially to the working axis of rotation (4) or perpendicular to the milling edge (5), wherein the base body (3) comprises one or more shoulder segments (13) between milling edges (5) adjacent in the circumferential direction (U), wherein the contour of the shoulder segments (13) at least partially follows the milling edge profile (P), and each shoulder segment (13) extends in the circumferential direction (U) with respect to the working axis of rotation (4) between a milling edge (5) and / or between the chip base (9, 10, 10') associated with the milling edge (5) and a flank edge (14) adjacent to the milling edge (5) in the working direction of rotation (U). [12] Milling tool (1) according to one of claims 1 to 11, wherein with respect to at least one axial position along the working axis of rotation (4) in the circumferential direction (U) of the working axis of rotation (4), a plurality of successive milling edge sections (5.1 - 5.4) are formed, and the base body (6) has elevations, depressions and / or flat and / or cylindrical sections (13) extending in the circumferential direction (U) between milling edge sections (5.1 - 5.4) adjacent in the circumferential direction (U), which are at the same, at least partially at a lower or higher radial level than the respectively adjacent chip space base (9, 10, 10') and / or have a decreasing, increasing or constant radial height, and / or wherein the base body (3) has a pagoda-like shape. [13] Milling tool (1) according to one of claims 1 to 9, comprising a base body (3), orif dependent on claim 9, the base body (3), wherein the base body (3) has a plurality of coolant and / or lubricant outlet openings (16), which are preferably oriented radially to the working axis of rotation (4), wherein the outlet openings (16) are optionally each arranged at least partially between a milling edge (5) and / or a chip space (9, 10, 10') and a flank edge (14) arranged upstream in the working direction of rotation (R), wherein opening planes of the outlet openings (16), viewed radially to the working axis of rotation (4), are optionally at the same height or at least partially higher than the respectively associated chip space base (9, 10, 10'), wherein, if dependent on claim 11, the coolant and / or lubricant outlet openings are optionally located within the shoulder segments (13), and wherein at least two of the coolant and / or lubricant outlet openings are arranged at radially different heights. [14] Method for producing a milling tool (1) which is made in one piece from a uniform material, with at least one milling edge (5) and a chip space (7) associated with the milling edge (5), wherein the milling edge (5) has a milling edge profile (P) with a sectionally non-linear course, comprising the following steps: - Providing a milling tool blank; - producing the at least one milling edge (5) and the associated chip space (7) on the milling blank by material removal, wherein - the material removal takes place in such a way that in the finished milling tool (1) a radial or vertical distance between the milling edge (5) and the chip space base (9, 10, 10') is at least partially substantially constant, and that on at least one of the at least one milling edge (5) a flank (15) extends opposite to the working direction of rotation (R) of the milling tool (1), and a pitch angle (T) defined by the milling edges (5) is three to 20 times the circumferential angle assigned to the flank (15). [15] Method according to claim 14, wherein a milling method is used for material processing, and / or wherein the material removal is carried out in such a way that each of the milling edges (5) is formed on a milling lug projecting relative to a base body (6), and the contour of the base body (6) between circumferentially adjacent milling lugs (5) is formed by material removal corresponding to the milling edge profile (P).

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