Milling tools and tool bodies for milling tools

Abstract

The present invention relates to a milling tool (101) comprising a tool body (102) and interchangeable cutting inserts (109a-h) mounted in associated insert seats (108a-h) successively arranged at the front end (103) of the tool body. The insert seats are unevenly distributed within the tool body to provide different angular distances between the cutting edges (113) of each pair of successive cutting inserts. The first insert seat (108a) is configured to keep the cutting edge of the first cutting insert (109a) axially forward of the cutting edges of the other inserts (109b-h), such that the angular distance between the first cutting insert and the insert immediately preceding it is smaller than the angular distance between any other pair of successive cutting inserts. The present invention also relates to a tool body (102) for such a milling tool (101).

Description

Technical Field

[0001] The present invention relates to a milling tool described at the beginning of claim 1 and a tool body described at the beginning of claim 14.

[0002] This type of milling tool, also called a milling cutter, is for chip removal machining of a metal workpiece. While rotating the tool body in a predetermined direction around the central longitudinal axis, the effective cutting edge of the cutting insert attached to the tool body is brought into contact with the workpiece, and by shaving thin chips of material from the workpiece with each rotation, it is for chip removal machining.

[0003] A milling tool is usually attached to a computer numerical control (CNC) machine and driven by the computer numerical control machine, and can be a milling tool for face milling or square shoulder milling.

Background Art

[0004] During a cutting operation, there is a dynamic interaction between the machine, the cutting tool attached to the machine, and the workpiece. Movements in various directions, sometimes simultaneous by various components, and high cutting forces cause vibrations in these components, which can have an adverse effect on the quality of the machining operation. Vibrations can lead to several problems including reduced accuracy, deteriorated surface finish, increased tool wear, and even damage to the workpiece or the machine and / or the cutting tool itself. Various cutting operations are associated with various degrees of vibration tendency. This is particularly due to the type of material being processed, the dimensions of the workpiece, especially the thickness of the material, and the shape cut out in the workpiece.

[0005] In milling operations, two main types of vibrations are observed. The first type is called forced vibration. This type of vibration can be described as periodic, containing frequency components influenced by the tooth passage frequency, which is affected by the machine spindle speed and the number of teeth / cutting inserts in the tool, when the cutting tool has an angularly uniform pitch, i.e., when the angular distance between adjacent cutting inserts in each pair attached to the tool body is equal. In this case, the vibration amplitude is often moderate and is considered acceptable. However, if this is not the case, the solution to the problem is strictly found in reducing the cutting parameters and / or increasing the rigidity of the cutting tool. In light of this, it should be emphasized that damping solutions do not contribute to reducing the amplitude of this type of vibration.

[0006] The second type of vibration is called regenerative vibration or chatter. This type of vibration often has an immeasurable impact on machining operations, resulting in poor surface finish and the risk of damage to both the cutting tool and the machine. Chatter itself is characterized by a rapid increase in vibration amplitude. In the initial stages, the amplitude increases exponentially, and then the vibration amplitude stabilizes at a point where the cutting tool eventually begins to jump into or out of the cutter.

[0007] Methods commonly used to reduce this second type of vibration caused by milling operations include reducing the cutting force by reducing the feed rate, increasing the speed or RPM (revolutions per minute), or reducing the amount of chips per cutting insert by reducing the axial or radial depth of cut. While these methods reduce vibration, they also mean that the speed of the milling operation decreases, resulting in reduced efficiency. Furthermore, reducing the chip load can also be detrimental to the milling tool. Other commonly used methods attempt to improve the rigidity and stability of the milling tool and workpiece as much as possible, some examples of which include using a larger diameter milling tool and improving the fixtures that hold the workpiece.

[0008] Numerous attempts have been made to create special milling tools that reduce vibration, but the results have been mixed. One known solution is to use a milling tool that includes a damped tool body. While functionally sufficient, this solution is expensive and not suitable for all types of milling operations.

[0009] Other known solutions involve embedding irregularly placed components or parts in the milling tool to prevent vibration resonance, such as cutting inserts at different distances from each other, cutting inserts of different shapes, or cutting inserts at different radial positions relative to each other, thereby preventing the amplitude from increasing to a critical level. These solutions often involve a trade-off between vibration reduction and wear / tool ​​life. That is, the solution that provides the greatest vibration reduction effect will substantially shorten tool life, and vice versa, because the milling tool components that contribute most to disrupting the vibration pattern, such as cutting inserts of different sizes and / or shapes, are also subjected to heavy loads and wear.

[0010] U.S. Patent Application Publication No. 20220055125 discloses an example of such a solution, namely, a milling tool that includes stepped cutting inserts between each pair of consecutive fixed cutting inserts when viewed in the rotational direction of the milling tool, the stepped cutting inserts are further arranged in a zigzag pattern along the circumference of the tool body when viewed in the rotational direction, namely, all other cutting inserts when viewed in the rotational direction have different axial and different radial positions relative to the fixed cutting inserts, thereby preventing increased vibration and maintaining cutting force, and thereby keeping wear on the individual cutting inserts as low as possible.

[0011] Another solution of this kind is disclosed in European Patent Application Publication No. 3321017, which describes a milling tool with two different types of cutting inserts, in which the cutting edges or parts thereof of the cutting inserts are positioned in various axial positions, in particular to reduce vibration.

[0012] Efforts are constantly being made to continuously improve this type of product, and there is still much to be done in this field. There is a particular demand for milling tools that can more effectively prevent vibration tendencies during cutting operations without significantly shortening tool life. [Overview of the Initiative]

[0013] The object of the present invention is to provide a milling tool of the type defined at the beginning, which is an improvement over such milling tools already known in at least several respects, for example, with respect to vibration prevention, surface finish on the workpiece, economic and environmental aspects during the manufacture and use of the tool, and / or the life of the tool as a result of wear on various parts of the tool during machining.

[0014] The present invention relates to a milling tool, A tool body having a front end and a rear end on the opposite side, the rear end being configured for attachment to a machine such as a CNC machine, and the longitudinal axis of the center of the tool body extending between the front and rear ends of the tool body, At least three interchangeable cutting inserts, each having at least one cutting edge, At least three insert seats are arranged in succession at the front end of the tool body and are distributed circumferentially around the tool body, and each of the at least three insert seats is configured to accommodate one of the cutting inserts, Equipped with, Each cutting insert is configured to be detachably mounted to the tool body in one of the insert seats located at a fixed position in the axial direction of the tool body, and each cutting insert has at least one of its cutting edges as an effective cutting edge when mounted in the tool body, and at least three insert seats are unevenly distributed in the circumferential direction of the tool body to provide the milling tool with unequal angular distances between the effective cutting edges of each pair of consecutive cutting inserts when at least three cutting inserts are mounted in the tool body. When at least three cutting inserts are mounted within the tool body, the first insert seat of at least three insert seats is configured to accommodate and hold the first cutting insert of at least three cutting inserts in a fixed position, and to maintain such that the axial foremost effective cutting edge of the first cutting insert defines the axial foremost part of the milling tool, and is positioned forward of the axial foremost effective cutting edges of at least most of the other cutting inserts in the longitudinal direction of the tool body, viewed from the rear end to the front end of the tool body. A milling tool in which, when at least three cutting inserts are mounted within the tool body, at least three insert seats are further dispersed such that, in the circumferential direction of the tool body, the angular distance between the effective cutting edge of the first cutting insert and the effective cutting edge of the insert immediately preceding the first cutting insert, as viewed in the intended rotational direction of the tool body, is smaller than the angular distance between the effective cutting edges of any other pair of consecutive cutting inserts among the at least three cutting inserts. This is solved by providing [a solution].

[0015] This configuration of at least three insert seats and cutting inserts within the milling tool implies effective vibration damping, as the axially protruding first cutting insert prevents resonance of the oscillating motion between the workpiece and the milling tool. The additional cutting force that would normally be applied to the axially protruding cutting insert is balanced by the relative positioning of this cutting insert and the angular distribution of the cutting insert along the circumference of the tool body. In short, the axially protruding first cutting insert reduces vibration, and its angular positioning relative to the insert immediately in front of it, viewed in the intended rotational direction of the tool body, minimizes and reduces excess wear on the tool body, resulting in a milling tool with efficient vibration suppression and a good service life.

[0016] According to one embodiment of the present invention, each of at least three insert seats includes an axial support surface, the axial support surface being configured to cooperate with the adjacent rear surface of the relevant cutting insert among the at least three cutting inserts when mounted within the insert seat, the rear side of the cutting insert is defined as the side facing away from the front end of the tool body toward the rear end when the cutting insert is in the mounting position, thereby providing the relevant cutting insert among the cutting inserts with an axial support and a fixed axial position, and defining a rear stopper in the axial direction of the tool body for the relevant cutting insert among the cutting inserts, thereby defining the axial position of the axially foremost effective cutting edge of the cutting insert when the cutting insert is mounted on the tool body, the axial support surface of the first insert seat is positioned forward of the axial support surfaces of at least most of the other insert seats among the at least three insert seats, viewed from the rear end to the front end of the tool body in the longitudinal direction of the tool body. This facilitates the installation and replacement of cutting inserts for the machine operator and ensures that the first cutting insert is securely held in the mounting position.

[0017] According to another embodiment of the present invention, when at least three cutting inserts are mounted in the tool body, the first insert seat is positioned forward of at least most of the other insert seats in the longitudinal direction of the tool body, viewed from the rear end to the front end of the tool body, thereby holding the first cutting insert of the at least three cutting inserts in a fixed position such that its axial foremost effective cutting edge defines the axial foremost end of the milling tool, and is positioned forward of at least most of the other cutting inserts in the longitudinal direction of the tool body, viewed from the rear end to the front end of the tool body, such that the first cutting insert is positioned such that its axial foremost effective cutting edge defines the axial foremost end of the milling tool. This structure provides a tool body that is easy to manufacture, cost-effective, and easy to use due to the minimal number of loose parts, and the machine operator does not need to adjust the cutting inserts to position them correctly. Furthermore, the axially forward-positioned first insert seat ensures that the first cutting insert remains in a stable position during use of the milling tool.

[0018] According to another embodiment of the present invention, for any number of at least three cutting inserts included in a milling tool, when at least three cutting inserts are mounted in the tool body, one or fewer of the other cutting inserts have their effective cutting edge's axial foremost position in the longitudinal direction of the tool body at the same axial position as the axial foremost position of the first cutting insert. This means that in any case, i.e., for any number of the cutting inserts, no more than two cutting inserts extend further axially forward than the other cutting inserts, thereby ensuring an effective vibration damping effect of the milling tool.

[0019] In another embodiment of the present invention, when at least three cutting inserts are mounted within the tool body, the first insert seat is configured to maintain such that the axially foremost effective cutting edge of the first cutting insert is located forward of the axially foremost effective cutting edge of each of the other cutting inserts, when viewed from the rear to the front of the tool body in the longitudinal direction of the tool body. This means that in any case, i.e., with any number of the cutting inserts, no more than one insert extends further axially forward than the others, thereby ensuring a more advantageous vibration damping effect of the milling tool.

[0020] In another embodiment of the present invention, when at least three cutting inserts are mounted within the tool body, at least three insert seats and at least three cutting inserts are arranged such that all of the at least three cutting inserts, except for the first cutting insert, have the axial foremost effective cutting edge in the same axial position when viewed in the longitudinal direction of the tool body. This results in a cost-effective milling tool that is easy to manufacture and use. In short, it is a milling tool that functions basically the same as a "regular" milling tool but has vibration damping characteristics that do not significantly shorten the tool's lifespan.

[0021] In another embodiment of the present invention, when at least three cutting inserts are mounted within the tool body, the first insert seat is configured such that the axial foremost effective cutting edge of the first cutting insert is located at least 0.05 mm, preferably at least 0.06 mm, more preferably 0.07 mm, and even more preferably 0.07 mm forward of the axial foremost effective cutting edges of the other cutting inserts among the at least three cutting inserts, when viewed from the rear end to the front end of the tool body in the longitudinal direction of the tool body. These dimensions have been shown to be advantageous in providing the desired effect of the present invention, namely effective vibration damping characteristics, to the milling tool without significantly shortening the life of the milling tool.

[0022] According to another embodiment of the present invention, at least one cutting edge of each of the at least three cutting inserts has a surface wipe portion, and each of the at least three cutting inserts has the same length. According to another embodiment of the present invention, at least three cutting inserts are identical in external shape, or at least substantially identical in external shape. This makes it easier for machine operators to attach and replace the cutting inserts to the tool body, and is cost-effective in terms of manufacturing and when customers purchase inserts for milling tools.

[0023] According to another embodiment of the present invention, there are at least three insert seats, numbering n in total, and at least three cutting inserts, numbering n in total, equal to the number of insert seats, where n is an integer from 3 to 12. The effects of the present invention have been shown to be particularly advantageous in milling tools that include the above number of cutting inserts.

[0024] According to another embodiment of the present invention, when n cutting inserts are mounted in the tool body, the n insert seats are arranged in the circumferential direction of the tool body such that the difference between the angular distance between the effective cutting edge of the first cutting insert and the effective cutting edge of the insert immediately preceding the first cutting insert as viewed in the intended rotation direction (R) of the tool body, and the angular distance between the effective cutting edges of a pair of consecutive cutting inserts among the n cutting inserts having the second smallest angular distance between the effective cutting edges of all pairs of consecutive cutting inserts among the n cutting inserts is at least TIFF2026522002000002.tif10170 degrees, and are dispersed such that where x is 0 when 7 ≤ n ≤ 10, x is 0.5 when 5 ≤ n ≤ 6 or 11 ≤ n ≤ 12, and x is 2 when 3 ≤ n ≤ 4.

[0025] The above relationship between the maximum angular distance and the minimum angular distance between pairs of consecutive cutting inserts in the tool body has been proven to be particularly advantageous for achieving the desired effects of the present invention, namely, the maximum vibration damping effect and the minimum wear in a milling tool.

[0026] According to another embodiment of the present invention, when n cutting inserts are mounted in the tool body, the n insert seats are arranged in the circumferential direction of the tool body such that the difference between the angular distance between the effective cutting edge of the first cutting insert and the effective cutting edge of the insert immediately preceding the first cutting insert as viewed in the intended rotation direction (R) of the tool body, and the angular distance between the effective cutting edges of a pair of consecutive cutting inserts among the n cutting inserts having the second smallest angular distance between the effective cutting edges of all pairs of consecutive cutting inserts among the n cutting inserts is at least TIFF2026522002000003.tif10170 degrees, and are dispersed such that where y is 0.2 when 7 ≤ n ≤ 12, y is 0.5 when 5 ≤ n ≤ 6, and y is 1 when 3 ≤ n ≤ 4.

[0027] The above relationship between the maximum angular distance and the second smallest angular distance between pairs of consecutive cutting inserts within the tool body has proven particularly advantageous for providing the effects desired by the present invention, namely, maximum vibration damping effect and minimum wear in the milling tool.

[0028] According to another embodiment of the present invention, when n cutting inserts are mounted within the tool body, the n insert seats are distributed in the circumferential direction of the tool body such that the angular distance between the effective cutting edges of each pair of consecutive cutting inserts is different from the angular distance between the effective cutting edges of any other pair of consecutive cutting inserts. This distribution of insert seats within the tool body further improves the vibration damping effect of the milling tool.

[0029] According to another embodiment of the present invention, the milling tool is a milling tool for square shoulder milling.

[0030] According to another embodiment of the present invention, the milling tool is a milling tool for face milling.

[0031] The present invention also relates to a tool body for a milling tool as described in the appended independent claims. The realization of such a tool body and the advantages of such a tool body are clearly evident from the above and following descriptions of embodiments of the milling tool according to the present invention.

[0032] Further advantages and favorable features of the present invention will become apparent from the detailed description of the embodiments below. [Brief explanation of the drawing]

[0033] In the following, embodiments of the present invention, as described in the attached drawings, will be specifically explained.

[0034] [Figure 1]This is a perspective view from below and to the side of a milling tool according to the first embodiment of the present invention for square shoulder milling, in which five cutting inserts are mounted inside the tool body. [Figure 2] Figure 1 is a partially exploded perspective view of a milling tool, showing how the cutting insert is mounted to the corresponding insert seat within the tool body. [Figure 3] Figure 1 is a view of the milling tool from below, showing the front end of the tool body equipped with the cutting insert. [Figure 4] Figure 3 is a side view of the milling tool shown in Figure 1, viewed from the direction indicated by "IV". [Figure 5] This is a perspective view from below and to the side of a milling tool according to a second embodiment of the present invention for face milling, in which eight cutting inserts are mounted inside the tool body. [Figure 6] Figure 5 is a partially exploded perspective view of a milling tool, showing how the cutting insert is mounted to the corresponding insert seat within the tool body. [Figure 7] Figure 5 shows a view of the milling tool from below, indicating the front end of the tool body equipped with the cutting insert. [Figure 8] This is a side view of the milling tool shown in Figure 5, viewed from the direction indicated as "VIII" in Figure 7. [Modes for carrying out the invention]

[0035] Two different embodiments of the milling tool 1, 101 according to the present invention each include a tool body 2, 102 according to the present invention, which are shown in Figures 1 to 8. Hereinafter, the milling tool and tool body according to the present invention will be described with reference to all of these drawings.

[0036] Figures 1 to 4 show milling tool 1 according to the present invention for square shoulder milling, in other words, square shoulder milling tool or square shoulder milling cutter, and Figures 5 to 8 show milling tool 101 according to the present invention for face milling, in other words, face milling tool or face milling cutter. However, the effect of the inventive features is the same or at least substantially the same for both types of milling tools, and it is not necessary to describe in detail the same or corresponding features for each of these embodiments, but components and parts described for one of the milling tools, i.e., one of the two embodiments, which are indicated by corresponding reference numerals (however, reference numerals in the 100s) on the other milling tool, have the same or corresponding functions and effects for the other milling tool, i.e., the other embodiments shown, unless otherwise specified.

[0037] The milling tool 1 shown in Figures 1 to 4 includes a tool body 2, which has a front end 3 and an opposite rear end 4 connected to a cylindrical or at least substantially cylindrical envelope surface 5. The rear of the tool body 2 forms a connecting member 6, through which the tool body can be attached to a machine, such as the rotating spindle of a CNC milling machine, either directly or via an intermediate tool holder. The central longitudinal axis 7 of the tool body 2 extends between the rear end 4 and the front end 3 of the tool body, and this central longitudinal axis coincides with the rotation axis of the milling tool 1. Therefore, the axial directions of the tool body and the milling tool are the same as their respective longitudinal directions.

[0038] At least three, and in this embodiment five, insert seats 8a to e are provided on the front of the tool body 2. These five insert seats 8a to e are arranged sequentially on the front end 3 of the tool body and are distributed in the circumferential direction of the tool body 2. Each insert seat 8a to e is configured to receive and accommodate its respective replaceable cutting insert 9a to e. Accordingly, each cutting insert 9a to e is configured to be detachably attached to the tool body 2 in one of the insert seats 8a to e, which are fixed in a position viewed in the axial direction of the tool body. More specifically, each cutting insert is provided with a central hole 10, and a mounting screw 11 is passed through this central hole 10 to fix it in the screw hole 12 provided in the insert seat 8a to e, thereby attaching the cutting insert to the fixed position within the insert seat (see Figure 2).

[0039] "Fixed position as seen in an axial direction" here means that the cutting inserts 9a to e in the fixed position are not movable or adjustable in any way in the axial direction of the tool body 2, i.e., in the longitudinal direction of the tool body, either from the rear end to the front end of the tool body or in the opposite direction, and are positioned in a fixed axial position relative to the tool body in the longitudinal direction of the tool body. In other words, in all embodiments of the present invention, the cutting inserts 9a to e are immovably mounted within the insert seats 8a to e of the tool body 2, and the insert seats 8a to e are immovably and fixedly positioned within the tool body 2.

[0040] The cutting inserts 9a to e are replaceable; that is, the cutting inserts 9a to e are detachably mounted in the fixed positions described above during the use of the milling tool 1 in a milling operation. When one of the cutting edges of a cutting insert wears out, the insert is released from its fixed position by loosening the mounting screw 11 and indexed to reveal a new, unused cutting edge. If no such cutting edge exists, the cutting insert is replaced with a new one.

[0041] Accordingly, each cutting insert 9a-e has at least one cutting edge 13, which is an active cutting edge 13, i.e., a cutting edge positioned so that it can be used to cut material from a workpiece by rotating the tool body and bringing it into contact with the workpiece when the cutting insert is mounted in a fixed position within the associated insert seats 8a-e in the tool body 2. In the first embodiment shown, each cutting insert has two identical opposing cutting edges, that is, when the first cutting edge wears out, the insert can be indexed once to position the other opposing cutting edge as the active cutting edge before the entire insert has to be replaced with a new one. In either case, when the cutting insert 9a-e is in a fixed mounting position in the axial direction, one of its cutting edges 13 is positioned as the active cutting edge. The cutting inserts of the milling tool according to the present invention may have any number of cutting edges.

[0042] The cutting inserts 9a to e are identical in external shape, or at least substantially identical in external shape. That is, the inserts may have different base materials and / or coatings, but they have essentially the same dimensions, for example, the lengths of the surface wipe portions 20 included in the cutting edge 13 are equal.

[0043] The insert seats 8a to e are unevenly distributed in the circumferential direction of the tool body 2 when viewed in the intended rotational direction R of the tool body, thereby providing the milling tool 1 with different angular distances 14a to e between the effective cutting edges 13 of each pair of consecutive cutting inserts 9a to e when the cutting inserts 9a to e are mounted within the tool body 2, i.e., when each cutting insert is mounted within its associated insert seat (see Figure 7 in particular).

[0044] Consequently, the insert seats 8a to e are unevenly distributed around the longitudinal axis 7 of the tool body 2, resulting in non-uniform spacing between the cutting inserts 9a to e around the tool body, more specifically, between the effective cutting edges of the cutting inserts 9a to e. A milling tool with such a configuration of insert seats and cutting inserts is called a differential-pitched milling tool. Therefore, this arrangement is well known to those skilled in the art and will not be described in detail here. However, for the sake of explanation, the angular distance 14a to e between a pair of consecutive cutting inserts 9a to e is measured as the angle between imaginary lines drawn from the center of the tool body 2, i.e., the longitudinal axis 7 of the center, to a point in each cutting insert where the primary and secondary parts of the effective cutting edge intersect (referred to as the Pk point) (illustrated in Figures 3 and 7). In this regard, each cutting insert 9a to e is naturally included in two different pairs of consecutive cutting inserts, namely, one pair containing the cutting insert immediately in front of the tool body 2 as viewed from the intended rotational direction R, and the other pair containing the cutting insert immediately behind it.

[0045] Each insert seat 8a-e is positioned in the transition area between the front end 3 and the enveloping surface 5 or outer circumference of the tool body 2, and each insert seat 8a-e is open toward the front end 3 of the tool body 2, so that cutting inserts 9a-e mounted in the insert seat can protrude axially beyond the front end 3 of the tool body 2, and further, each insert seat 8a-e is open toward the front end 3 of the tool body 2, so that cutting inserts 9a-e mounted in the insert seat can protrude radially beyond the enveloping surface or outer circumference of the tool body 2. A tip pocket 15 is provided in the tool body 2 in front of each insert seat 8a-e when viewed in the intended rotational direction R of the tool body 2. In various embodiments of the present invention, each of the at least three insert seats may be positioned at the front end, or preferably in the transition area between the front end and the enveloping surface.

[0046] When the cutting inserts 9a to e are installed in the tool body 2, the first insert seat 8a of the insert seats 8a to e is configured to accommodate and hold the first cutting insert 9a in a fixed position, and to maintain such that the axial foremost effective cutting edge 13 of the first cutting insert 9a defines the axial foremost part of the milling tool 1, and that, in the longitudinal direction of the tool body 2, viewed from the rear end 4 to the front end 3 of the tool body 2, it is positioned forward of the axial foremost effective cutting edge 13 of at least most of the other cutting inserts 9b to e, and in this embodiment all of the other cutting inserts 9b to e. Accordingly, the first insert seat 8a is configured to maintain the axial foremost portion of the associated first cutting insert 9a in the form of a portion of its effective cutting edge 13 at a first axial position 16, which in the longitudinal direction of the tool body 2 is forward of the second axial position 17 where the foremost portions of the effective cutting edges 13 of all the other cutting inserts 9b-e are located, i.e., further away from the rear end 4 of the tool body 2. In other words, when all the cutting inserts 9a-e are mounted in the tool body 2, i.e., when they are held in their fixed positions by the associated insert seats 8a-e, the foremost portion of the first cutting insert 9a protrudes beyond the foremost portions of the other cutting inserts 9b-e, defining the axial foremost portion of the milling tool 1.

[0047] When the cutting inserts 9a to e are mounted in the tool body 2, the first insert seat 8a is configured to maintain that the axial foremost portion of the first cutting insert 9a is located at least 0.05 mm, preferably at least 0.06 mm, more preferably 0.07 mm, and even more preferably 0.07 mm forward of the axial foremost portion of the effective cutting edges 13 of the other cutting inserts 9b to e, when viewed from the rear end 4 to the front end 3 of the tool body 2 in the longitudinal direction of the tool body 2. When the cutting inserts 9a to e are mounted in the tool body 2, it is ensured that in any case the axial foremost portion of the effective cutting edge 13 of the first cutting insert 9a protrudes at least 0.01 mm, preferably at least 0.02 mm, and more preferably at least 0.03 mm beyond the axial foremost portion of the effective cutting edges 13 of the other cutting inserts 9b to e. More specifically, the minimum difference between the axial position of the axially foremost effective cutting edge 13 of the first cutting insert 9a and the axial position of the axially foremost effective cutting edges 13 of the other cutting inserts 9b-e, which is the minimum difference targeted and preferably achieved, is selected such that in any case it is ensured that the manufacturing tolerances of one of the at least three insert seats in the tool body and the associated cutting insert of the at least three cutting inserts do not completely negate the axial forward protrusion of the axially foremost effective cutting edge 13 of the first cutting insert 9a beyond the axially foremost effective cutting edges 13 of the other cutting inserts 9b-e.

[0048] These lengths are beneficial in providing the milling tool 1 with the desired vibration damping effect. In any case, the first cutting insert 9a should protrude at least 0.05 mm axially forward, but not by more than 0.1 mm, than the other cutting inserts 9b to e or at least the majority of the other cutting inserts. This is because exceeding this value would cause a rapid increase in wear on the first cutting insert 9a, impairing the beneficial effects of the present invention.

[0049] This axial forward positioning of the first cutting insert 9a by the first insert seat 8a is achieved by positioning the first insert seat 8a forward of at least most of the other insert seats 8b~e, and in this embodiment all of the other insert seats, when viewed in the longitudinal direction of the tool body 2 from the rear end 4 to the front end 3 of the tool body 2.

[0050] Each of the insert seats 8a to e includes an axial support surface 18, which is configured to cooperate with the adjacent rear surface 19 of the cutting insert 9a to e when mounted on the insert seats 8a to e. In this context, the rear side of the cutting insert is defined as the side facing away from the front end 3 of the tool body 2, towards the rear end 4, when the cutting insert 9a to e is in the mounting position. Thus, the rear side of the cutting insert is the side that faces the insert seat when the insert is mounted in the insert seat, in which case the insert is mounted facing the bottom of the insert seat. In other words, when the inserts 9a to e are released and indexed to have the other cutting edge 13 as an effective cutting edge, i.e., released, rotated 180 degrees, and mounted again in the fixed position, the side of the insert that was facing axially forward becomes the rear side after the rotation. Thus, the rear side is the side opposite to the side on which the currently effective cutting edge is provided.

[0051] The axial support surface 18 provides axial support and a fixed axial position to the relevant cutting insert among the cutting inserts, that is, by defining a rear stopper in the axial direction of the tool body 2 for the relevant cutting insert among the cutting inserts 9a to e that is mounted on its insert seat, and thereby provides axial support and a fixed axial position by determining the axial positions 16 and 17 of the axially foremost effective cutting edge 13 of the cutting insert when the cutting insert is mounted on the tool body. Accordingly, when all cutting inserts 9a to e are mounted within the tool body 2, the axial support surface 18 defining the rear stopper for the first cutting insert 9a within the first seat seat 8a is positioned forward of at least most of the other insert seats 8b to e, in this embodiment all of the other insert seats, when viewed from the rear end 4 to the front end 3 of the tool body 2 in the longitudinal direction of the tool body 2, and is thereby configured to hold the first cutting insert 9a in a fixed position such that the axial foremost portion of its effective cutting edge 13 defines the axial foremost portion of the milling tool 1, and is positioned forward of the axial foremost portions of the effective cutting edges 13 of the other cutting inserts 9b to e when viewed from the rear end 4 to the front end 3 of the tool body 2 in the longitudinal direction of the tool body 2. In addition to the axial support surface 18, all other features of the first insert seat 8a, such as the screw hole 10 and various other support surfaces, are also located axially forward of the corresponding features of the other insert seats 8b to e. That is, the first insert seat 8a has the same or at least substantially the same external shape as the other insert seats 8b to e, but is positioned more axially forward within the tool body 2.

[0052] In the shown embodiment, only one of the cutting inserts, cutting insert 9a, is positioned axially forward relative to the other inserts 9b-e. However, it is possible to have more than one such insert that protrudes axially forward, for example, two or more inserts whose axial foremost portions are held at the first axial position 16 when mounted on the tool body 2. In such a case, two or more insert seats are positioned forward of at least most of the other insert seats in the longitudinal direction of the tool body 2, viewed from the rear end 4 to the front end 3 of the tool body 2. However, the number of such axially protruding inserts should in any case be smaller than the number of other inserts, i.e., inserts whose foremost portions do not define the axial foremost position of the milling tool 1. A smaller total number of inserts defining the axial position of the foremost part of the milling tool results in a better vibration damping effect. In a preferred embodiment (not shown), the axial foremost portions of up to two inserts are positioned axially forward of the axial foremost portions of the other inserts. Since inserts that protrude axially forward need to be a minority of the total number of inserts, such a milling tool would need to have at least five cutting inserts 9a to e. However, in most cases, it is preferable that, as in the embodiment shown in the figure, only one of the cutting inserts, cutting insert 9a, has its axial foremost portion positioned axially forward of all the other cutting inserts 9b to e.

[0053] In the embodiment shown, when at least three cutting inserts are mounted in the tool body, all other cutting inserts 9b-e, except for the first cutting insert 9a, are arranged such that the axial foremost portion of the cutting edge 13 is effective at the same axial position 17 when viewed in the longitudinal direction of the tool body 2. This is evident from Figures 4 and 8. While this is a preferred embodiment, it is also possible that the other cutting inserts 9b-e are located at different axial positions along the tool body; for example, one or more cutting inserts may be located axially rearward at the front end 3 of the tool body 2 compared to some of the other cutting inserts.

[0054] When the cutting inserts 9a to e are mounted within the tool body 2, the insert seats 8a to e are further dispersed in the circumferential direction of the tool body 2 such that the angular distance 14a between the effective cutting edge 13 of the first cutting insert 9a and the effective cutting edge of the insert 9e immediately preceding the first cutting insert, as viewed in the intended rotational direction R of the tool body, is smaller than the angular distance 14b to e between any other pair of effective cutting edges of the consecutive cutting inserts 9a to e (see Figure 3, and especially Figure 7). Due to this configuration of the inserts 9a to e within the tool body 2, the first cutting insert 9a will be exposed to the minimum cutting force during the cutting operation of all cutting inserts, as if all cutting inserts were positioned in exactly the same axial position. Such positioning of the first cutting insert 9a balances or reduces any extra cutting force that would be added due to its axial forward position. In other words, the inventors have found a way to use the first cutting insert 9a as a vibration damper while protecting it from excessive wear, thereby maintaining a good lifespan for both the cutting insert and the milling tool 1.

[0055] The inventors have further discovered a specific relationship between the angular distances 14a to e between the effective cutting edges of a pair of consecutive cutting inserts, which results in an optimized inventive effect, particularly in terms of a favorable vibration damping effect and low wear on the first cutting insert 9a.

[0056] More specifically, when n cutting inserts are mounted within the tool body 2, for each case there are n insert seats 8a to e and cutting inserts 9a to e, that is, when n insert seats and n cutting inserts are provided within the tool body 2, where n is an integer from 3 to 12, preferably, in the circumferential direction of the tool body 2, the difference between the angular distance 14a between the effective cutting edge of the first cutting insert 9a and the effective cutting edge of the insert 9e immediately preceding the first cutting insert, as viewed in the intended rotational direction R of the tool body 2, and the angular distance between the effective cutting edges of a pair of consecutive cutting inserts having the maximum angular distance between their effective cutting edges is at least It is distributed so that TIFF2026522002000004.tif10170 degrees, However, x is 0 when 7 ≤ n ≤ 10, 0.5 when 5 ≤ n ≤ 6 or 11 ≤ n ≤ 12, and 2 when 3 ≤ n ≤ 4.

[0057] In other words, the difference between the minimum and maximum angular distances between the effective cutting edges of a pair of consecutive cutting inserts mounted within the tool body 2 should be at least 8.7 degrees when there are three cutting inserts arranged consecutively at the front end 3 of the tool body 2 of the milling tool 1, at least 7 degrees when there are four cutting inserts, at least 4.5 degrees when there are five cutting inserts, at least 3.8 degrees when there are six cutting inserts, at least 2.9 degrees when there are seven cutting inserts, at least 2.5 degrees when there are eight cutting inserts, at least 2.2 degrees when there are nine cutting inserts, at least 2 degrees when there are ten cutting inserts, at least 2.3 degrees when there are eleven cutting inserts, and at least 2.2 degrees when there are twelve cutting inserts. Therefore, in the milling tool 1 shown in Figures 1 to 4, which includes five cutting inserts 9a to e, the difference between the minimum angular distance 14a to e and the maximum angular distance 14a to e should be at least 4.5.

[0058] Furthermore, preferably, when n cutting inserts are mounted within the tool body 2, the difference between the effective cutting edge of the first cutting insert 9e and the effective cutting edge of the insert 9e immediately preceding the first cutting insert 9a, as viewed in the intended rotational direction R of the tool body, and the angular distance between the effective cutting edges of a pair of consecutive cutting inserts having the second smallest angular distance between the effective cutting edges of all pairs of consecutive cutting inserts among the n cutting inserts is at least The distribution is such that TIFF2026522002000005.tif10170 degrees, however, y is 0.2 when 7≦n≦12, y is 0.5 when 5≦n≦6, and y is 1 when 3≦n≦4.

[0059] In other words, the difference between the minimum angular distance and the second smallest angular distance between the effective cutting edges of a pair of consecutive cutting inserts mounted within the tool body 2 should be at least 2.7 degrees when there are three cutting inserts arranged consecutively at the front end 3 of the tool body 2 of the milling tool 1, at least 1.25 degrees when there are four cutting inserts, at least 1.5 degrees when there are five cutting inserts, at least 1.3 degrees when there are six cutting inserts, at least 0.9 degrees when there are seven cutting inserts, at least 0.8 degrees when there are eight cutting inserts, at least 0.8 degrees when there are nine cutting inserts, at least 0.7 degrees when there are ten cutting inserts, at least 0.7 degrees when there are eleven cutting inserts, and at least 0.6 degrees when there are twelve cutting inserts. Therefore, in the milling tool 1 shown in Figures 1 to 4, which includes five cutting inserts 9a to e, the difference between the minimum angular distance 14a to e and the second smallest angular distance 14a to e should be at least 1.5.

[0060] Furthermore, when the cutting inserts are mounted within the tool body 2, the insert seats 8a to e are distributed such that, in the circumferential direction of the tool body 2, the angular distances 14a to e between the effective cutting edges 13 of each pair of consecutive cutting inserts 9a to e are different from the angular distances between the cutting edges of any other pair of consecutive cutting edges. This configuration further supports interference with harmonic vibrations occurring between the workpiece and the milling tool 1.

[0061] Accordingly, in the milling tool 1 according to the first embodiment, the angular distances 14a to e between the effective cutting edges 13 of the pair of consecutive cutting inserts 9a to e can be, for example, 69 degrees, 71 degrees, 72 degrees, 73 degrees, and 75 degrees.

[0062] The inventive features described above also have essentially the same function in the milling tool 101 shown in Figures 5 to 8. As already mentioned, this milling tool is for face milling. This milling tool is equipped with eight insert seats 108a to h and eight cutting inserts 109a to h. When the cutting inserts 109a to h are mounted in the tool body 102, the axial foremost part of the first cutting insert 109a is held in a fixed position in the first insert seat 108a such that, in the longitudinal direction of the tool body 102, it is positioned axially forward of at least the majority of the axial foremost parts of the other cutting inserts 109b to h, which in this embodiment is the axial foremost part of all of them. The inserts of the face milling tool 101 have a different shape from those of the square shoulder milling tool 1, and the total number of usable cutting edges is 14 instead of 2. The number of cutting inserts 109a~h on this milling tool 101 means that the difference between the minimum angular distance 114a~h and the maximum angular distance 114a~h should be at least 2.5 degrees. At the same time, the difference between the minimum angular distance 114a~h and the second smallest angular distance 114a~h should be at least 0.8 degrees.

[0063] Accordingly, the angular distances 114a to h between the effective cutting edges 113 of the pair of consecutive cutting inserts 109a to h in the milling tool 101 according to the second embodiment can be, for example, 42 degrees, 43 degrees, 43.5 degrees, 45 degrees, 45.5 degrees, 46 degrees, 47 degrees, and 48 degrees.

[0064] Naturally, the present invention is not limited in any way to the embodiments described above. On the contrary, those skilled in the art will see many possibilities for modifications without departing from the basic concept of the invention as defined in the appended claims.

[0065] The number of insert seats and associated cutting inserts in the milling tool according to the present invention can be 3 to 12. However, it should be noted that such a milling tool, for example a deep shoulder milling tool, may have more than 12 cutting inserts in total, as long as it has 3 to 12 such insert seats and cutting inserts as defined above.

[0066] The statement that insert seats should be "unevenly distributed" to provide "irregular angular distances" between consecutive cutting inserts should be interpreted as meaning that at least all of the above angular distances are not the same, but that this covers the case where only one of the above angular distances is not the same as the others.

[0067] The axial foremost portion is understood to be the portion that defines the foremost portion of the tool or insert, both for that portion of the milling tool and for that portion of an individual cutting insert, when viewed longitudinally from the rear to the front of the tool body. However, this position may be shared by other components or parts, i.e., two inserts may each have a portion that defines the axial foremost portion of the milling tool, for example, two portions of the same cutting insert may be located in exactly the same axial position and both may define the axial foremost portion of the insert.

Claims

1. A milling tool (1,101), - A tool body (2, 102) having a front end (3, 103) and a rear end (4, 104) on the opposite side, wherein the rear end (4, 104) is configured for attachment to a machine such as a CNC machine, and the longitudinal axis (7, 107) of the center of the tool body (2, 102) extends between the rear end (4, 104) and the front end (3, 103) of the tool body (2, 102), - At least three interchangeable cutting inserts (9a-e, 109a-h), each of which cutting inserts (9a-e, 109a-h) has at least one cutting edge (13, 113), and - At least three insert seats (8a-e, 108a-h) are arranged in succession at the front end (3, 103) of the tool body (2, 102) and are distributed in the circumferential direction of the tool body (2, 102), wherein each of the at least three insert seats (8a-e, 108a-h) is configured to accommodate one of the cutting inserts (9a-e, 109a-h), Equipped with, Each cutting insert (9a to e, 109a to h) is configured to be detachably attached to the tool body (2, 102) within one of the insert seats (8a to e, 108a to h) located at a fixed position in the axial direction of the tool body (2, 102). Each cutting insert (9a to e, 109a to h) has at least one of the cutting edges (13, 113) as an effective cutting edge when it is mounted in the tool body (2, 102), In a milling tool (1, 101), the at least three insert seats (8a-e, 108a-h) are unevenly distributed in the circumferential direction of the tool body (2, 102) so as to provide the milling tool (1, 101) with unequal angular distances (14a-e, 114a-h) between the effective cutting edges (13, 113) of each pair of consecutive cutting inserts (9a-e, 109a-h) of the at least three cutting inserts (9a-e, 109a-h) when the at least three cutting inserts (9a-e, 109a-h) are mounted within the tool body (2, 102), When the at least three cutting inserts (9a to e, 109a to h) are mounted in the tool body (2, 102), the first insert seat (8a, 108a) of the at least three insert seats (8a to e, 108a to h) accommodates and holds the first cutting insert (9a, 109a) of the at least three cutting inserts (9a to e, 109a to h) in the fixed position, and the axial foremost portion of the effective cutting edge (13, 113) of the first cutting insert (9a, 109a) is the f The tool is configured to be positioned to define the axial foremost portion of the rice tool (1, 101), and to be maintained such that, in the longitudinal direction of the tool body (2, 102), when viewed from the rear end (4, 104) to the front end (3, 103) of the tool body (2, 102), it is positioned forward of the axial foremost portion of the effective cutting edges (13, 113) of at least the majority of the other cutting inserts (9b, e, 109b, h) of the at least three cutting inserts (9a, e, 109a, h), When the at least three cutting inserts (9a-e, 109a-h) are mounted within the tool body (2, 102), the at least three insert seats (8a-e, 108a-h) are such that, in the circumferential direction of the tool body (2, 102), the effective cutting edges (13, 113) of the first cutting inserts (9a, 109a) and the first cutting inserts (9a, 109a) as viewed in the intended rotational direction (R) of the tool body (2, 102) A milling tool (1, 101) characterized in that the angular distance (14a, 114a) between the effective cutting edge (13, 113) of the insert (9e, 109h) immediately preceding it is further dispersed such that it is smaller than the angular distance (14b, e, 114b, h) between the effective cutting edges (13, 113) of any other pair of consecutive cutting inserts (9a, e, 109a, h) among the at least three cutting inserts (9a, e, 109a, h).

2. Each of the at least three insert seats (8a-e, 108a-h) includes an axial support surface (18, 118), and the axial support surfaces (18, 118) are configured to cooperate with the adjacent rear surface (19, 119) of the relevant cutting insert among the at least three cutting inserts (9a-e, 109a-h) when mounted within the insert seat (8a-e, 108a-h), and when the cutting insert (9a-e, 109a-h) is in the mounting position, the rear side of the cutting insert (9a-e, 109a-h) is toward the rear end (4, 104) toward the tool body (2, 102) It is defined as the side facing away from the front end (3, 103), thereby providing the relevant cutting insert (9a-e, 109a-h) with axial support and a fixed axial position, and defining the axial rear stopper of the tool body (2, 102) for the relevant cutting insert (9a-e, 109a-h), thereby defining the axial foremost position of the effective cutting edge (13, 113) of the cutting insert when the cutting insert (9a-e, 109a-h) is mounted within the tool body (2, 102). The milling tool (1, 101) according to claim 1, characterized in that the axial support surfaces (18, 118) of the first insert seat (8a, 108a) are positioned forward of the axial support surfaces (18, 118) of at least most of the other insert seats (8b, e, 108b, h) of the at least three insert seats (8a, e, 108a, h), when viewed from the rear end (4, 104) to the front end (3, 103) of the tool body (2, 102) in the longitudinal direction of the tool body (2, 102).

3. When the at least three cutting inserts (9a-e, 109a-h) are mounted in the tool body (2, 102), the first insert seat (8a, 108a) is positioned in the longitudinal direction of the tool body (2, 102), viewed from the rear end (4, 104) to the front end (3, 103) of the tool body (2, 102), and thereby positions the first cutting insert (9a, 109a) of the at least three cutting inserts (9a-e, 109a-h) forward of at least the majority of the other insert seats (8b-e, 108b-h), and thereby positions the first cutting insert (9a, 109a) of the at least three cutting inserts (9a-e, 109a-h), The milling tool (1,101) according to claim 1 or 2, characterized in that the axial foremost portion of the effective cutting edge (13, 113) is positioned to define the axial foremost portion of the milling tool (1, 101), and is configured to be held in the fixed position such that, when viewed from the rear end (4, 104) to the front end (3, 103) of the tool body (2, 102) in the longitudinal direction of the tool body (2, 102), it is positioned forward of the axial foremost portion of the effective cutting edge (13, 113) of at least most of the other cutting inserts (9b, e, 109b, h) among the at least three cutting inserts (9a, e, 109a, h).

4. The milling tool (1, 101) according to any one of claims 1 to 3, characterized in that, for any number of the at least three cutting inserts (9a to e, 109a to h) included in the milling tool (1, 101), when the at least three cutting inserts (9a to e, 109a to h) are mounted in the tool body (2, 102), one or less of the other cutting inserts (9b to e, 109b to h) among the at least three cutting inserts (9a to e, 109a to h) has the axial frontmost portion (13, 113) of the effective cutting edge (13, 113) at the same axial position as the axial frontmost portion of the first cutting insert (9a, 109a) in the longitudinal direction of the tool body (2, 102).

5. A milling tool (1, 101) according to any one of claims 1 to 3, characterized in that when the at least three cutting inserts (9a to e, 109a to h) are mounted in the tool body (2, 102), the first insert seat (8a, 108a) is configured to maintain such that the axial foremost portion of the effective cutting edge (13, 113) of the first cutting insert (9a, 109a) is located forward of the axial foremost portion of the effective cutting edge (13, 113) of each of the other cutting inserts (9b to e, 109b to h) of the at least three cutting inserts (9a to e, 109a to h), when viewed from the rear end (4, 104) to the front end (3, 103) of the tool body (2, 102) in the longitudinal direction of the tool body (2, 102).

6. The milling tool (1, 101) according to claim 5, characterized in that when the at least three cutting inserts (9a to e, 109a to h) are mounted in the tool body (2, 102), the at least three insert seats (8a to e, 108a to h) and the at least three cutting inserts (9a to e, 109a to h) are arranged such that all of the at least three cutting inserts (9a to e, 109a to h), excluding the first cutting insert (9a, 109a), have the axially foremost portions of the effective cutting edges (13, 113) at the same axial position when viewed in the longitudinal direction of the tool body (2, 102).

7. When the at least three cutting inserts (9a-e, 109a-h) are mounted within the tool body (2, 102), the first insert seats (8a, 108a) are such that the axial foremost portion of the effective cutting edge (13, 113) of the first cutting insert (9a, 109a) is positioned such that, when viewed in the longitudinal direction of the tool body (2, 102) from the rear end (4, 104) towards the front end (3, 103) of the tool body (2, 102), The milling tool (1, 101) according to claim 6, characterized in that it is configured to be maintained so as to be located forward of the axial foremost part of the effective cutting edge (13, 113) of the other cutting inserts (9b-e, 109b-h) of the at least three cutting inserts (9a-e, 109a-h) by at least 0.05 mm, preferably at least 0.06 mm, more preferably 0.07 mm, and even more preferably 0.07 mm.

8. The milling tool (1, 101) according to any one of claims 1 to 7, characterized in that each of the at least three cutting inserts (9a to e, 109a to h) has at least one cutting edge (13, 113) with a surface wiping portion (20), and each of the surface wiping portions (20) of the at least three cutting inserts (9a to e, 109a to h) has the same length.

9. The milling tool (1, 101) according to claim 8, characterized in that the at least three cutting inserts (9a to e, 109a to h) have the same external shape or at least substantially the same external shape.

10. The milling tool (1, 101) according to any one of claims 1 to 9, characterized in that there are n of the at least three insert seats (8a to e, 108a to h), and there are n of the at least three cutting inserts (9a to e, 109a to h), where n is equal to the number of insert seats (8a to e, 108a to h) and n is an integer from 3 to 12.

11. When the n cutting inserts (9a-e, 109a-h) are installed in the tool body (2, 102), the n insert seats (8a-e, 108a-h) are positioned in the circumferential direction of the tool body (2, 102) such that the effective cutting edges (13, 113) of the first cutting inserts (9a, 109a) and the inserts (9e, 109h) immediately in front of the first cutting inserts (9a, 109a) are positioned in the intended rotational direction (R) of the tool body (2, 102). The difference between the angular distance (14a, 114a) between the effective cutting edges (13, 113) and the angular distance (14b-e, 114b-h) between the effective cutting edges (13, 113) of one pair of consecutive cutting inserts (9a-e, 109a-h) from the n cutting inserts (9a-e, 109a-h) that has the maximum angular distance between the effective cutting edges (13, 113) of all pairs of consecutive cutting inserts (9a-e, 109a-h) from the n cutting inserts (9a-e, 109a-h) is at least It is distributed so that it is in degrees, The milling tool (1, 101) according to claim 10, characterized in that x is 0 when 7 ≤ n ≤ 10, x is 0.5 when 5 ≤ n ≤ 6 or 11 ≤ n ≤ 12, and x is 2 when 3 ≤ n ≤ 4.

12. When the n cutting inserts (9a-e, 109a-h) are installed in the tool body (2, 102), the n insert seats (8a-e, 108a-h) are positioned in the circumferential direction of the tool body (2, 102) to have the effective cutting edges (13, 113) of the first cutting inserts (9a, 109a) and the effective cutting edges (9e, 109h) of the inserts (9e, 109h) immediately in front of the first cutting inserts (9a, 109a) when viewed in the intended rotational direction (R) of the tool body (2, 102). The difference between the angular distance (14a, 114a) between the cutting edges (13, 113) and the angular distance (14b-e, 114b-h) between the effective cutting edges (13, 113) of one pair of consecutive cutting inserts (9a-e, 109a-h) from the n cutting inserts (9a-e, 109a-h) having the second smallest angular distance between the effective cutting edges (13, 113) of all pairs of consecutive cutting inserts (9a-e, 109a-h) from the n cutting inserts (9a-e, 109a-h) is at least They are distributed so that they are in degrees, The milling tool according to claim 10 or 11, characterized in that y is 0.2 when 7 ≤ n ≤ 12, y is 0.5 when 5 ≤ n ≤ 6, and y is 1 when 3 ≤ n ≤ 4.

13. A milling tool (1, 101) according to any one of claims 10 to 12, characterized in that when the n cutting inserts (9a to e, 109a to h) are mounted in the tool body (2, 102), the n insert seats (8a to e, 108a to h) are distributed in the circumferential direction of the tool body (2, 102) such that the angular distances (14a to e, 114a to h) between the effective cutting edges (13, 113) of each pair of consecutive cutting inserts (9a to e, 109a to h) among the n cutting inserts (9a to e, 109a to h) are different from the angular distances (14a to e, 114a to h) between the effective cutting edges (13, 113) of any other pair of consecutive cutting inserts (9a to e, 109a to h) among the n cutting inserts (9a to e, 109a to h).

14. The tool body (2, 102) is intended to comprise at least three cutting inserts (9a-e, 109a-h) that are identical or at least substantially identical in external shape to form a milling tool (1, 101), each cutting insert having at least one cutting edge (13, 113), and the tool body (2, 102) is, The tool body (2, 102) has a front end (3, 103) and a rear end (104) on the opposite side, the rear end (4, 104) being configured for attachment to a machine such as a CNC machine, and the longitudinal axis (7, 107) of the center of the tool body (2, 102) extends between the rear end (4, 104) and the front end (3, 103) of the tool body (2, 102), the front end (3, 103) and the rear end (104) on the opposite side, At least three insert seats (8a-e, 108a-h) are arranged in succession at the front end (3, 103) of the tool body (2, 102) and are distributed in the circumferential direction of the tool body (2, 102), wherein each of the at least three insert seats (8a-e, 108a-h) is configured to accommodate one of the cutting inserts (9a-e, 109a-h) and hold it in a removable mounting position, in which the cutting insert (9a-e, 109a-h) is fixed to the tool body (2, 102) when viewed in the axial direction of the tool body (2, 102), and has one of the at least one cutting edge (13, 113) as an effective cutting edge, It has, When the at least three cutting inserts (9a-e, 109a-h) are mounted within the tool body (2, 102), the at least three insert seats (8a-e, 108a-h) are unevenly distributed in the circumferential direction of the tool body (2, 102) so as to provide the milling tool (1, 101) with unequal angular distances (14a-e, 114a-h) between the effective cutting edges (13, 113) of each pair of consecutive cutting inserts (9a-e, 109a-h) of the at least three cutting inserts (9a-e, 109a-h), in the tool body (2, 102), When the at least three cutting inserts (9a to e, 109a to h) are mounted in the tool body (2, 102), the first insert seat (8a, 108a) of the at least three insert seats (8a to e, 108a to h) accommodates and holds the first cutting insert (9a, 109a) of the at least three cutting inserts (9a to e, 109a to h) in the mounting position, and the axial foremost portion of the effective cutting edge (13, 113) of the first cutting insert (9a, 109a) is the The milling tool (1, 101) is positioned to define the foremost axial portion, and is maintained such that, in the longitudinal direction of the tool body (2, 102), when viewed from the rear end (4, 104) to the front end (3, 103) of the tool body (2, 102), it is positioned forward of the foremost axial portion of the effective cutting edges (13, 113) of at least most of the other cutting inserts (9b, e, 109b, h) among the at least three cutting inserts (9a, e, 109a, h). Each of the at least three insert seats (8a-e, 108a-h) includes an axial support surface (18, 118), and the axial support surface (18, 118) is configured to cooperate with the adjacent rear surface (19, 119) of the relevant cutting insert among the at least three cutting inserts (9a-e, 109a-h) when mounted within the insert seat (8a-e, 108a-h), and when the cutting insert (9a-e, 109a-h) is in the mounting position, the rear side of the cutting insert (9a-e, 109a-h) is toward the rear end (4, 104) toward the tool body (2, 102) It is defined as the side facing away from the front end (3, 103), thereby providing the relevant cutting insert (9a-e, 109a-h) with axial support and a fixed axial position, and defining the axial rear stopper of the tool body (2, 102) for the relevant cutting insert (9a-e, 109a-h), thereby defining the axial foremost position of the effective cutting edge (13, 113) of the cutting insert when the cutting insert (9a-e, 109a-h) is mounted within the tool body (2, 102). The axial support surfaces (18, 118) of the first insert seat (8a, 108a) are positioned forward of the axial support surfaces (18, 118) of at least most of the other insert seats (8b-e, 108b-h) of the at least three insert seats, when viewed from the rear end (4, 104) to the front end (3, 103) of the tool body (2, 102) in the longitudinal direction of the tool body (2, 102). When the at least three cutting inserts (9a-e, 109a-h) are mounted within the tool body (2, 102), the at least three insert seats (8a-e, 108a-h) are positioned such that, in the circumferential direction of the tool body (2, 102), the effective cutting edges (13, 113) of the first cutting inserts (9a, 109a) and the first cutting inserts (9a, 109a) are positioned such that, when viewed in the intended rotational direction (R) of the tool body (2, 102), the effective cutting edges (13, 113) of the first cutting inserts (9a, 109a) The tool body (2, 102) is further distributed such that the angular distance (14a, 114a) between the effective cutting edge (13, 113) of the insert (9e, 109h) immediately preceding it is smaller than the angular distance (14b-e, 114b-h) between the effective cutting edges (13, 113) of any other pair of consecutive cutting inserts (9a-e, 109a-h) among the at least three cutting inserts (9a-e, 109a-h).

15. When the at least three cutting inserts (9a-e, 109a-h) are mounted in the tool body (2, 102), the first insert seat (8a, 108a) is positioned in the longitudinal direction of the tool body (2, 102), viewed from the rear end (4, 104) to the front end (3, 103) of the tool body (2, 102), and thereby the first cutting insert (9a, 109a) of the at least three cutting inserts (9a-e, 109a-h) The tool body (2, 102) according to claim 14, characterized in that the tool body (2, 102) is held in a fixed position such that the axial foremost portion of the effective cutting edge (13, 113) is positioned such that it defines the axial foremost portion of the milling tool (1, 101), and that, in the longitudinal direction of the tool body (2, 102), when viewed from the rear end (4, 104) to the front end (3, 103) of the tool body (2, 102), it is positioned forward of the axial foremost portion of the other cutting inserts (9b, e, 109b, h) of the at least three cutting inserts (9a, e, 109a, h).

16. Of the at least three insert seats (8a to e, 108a to h), all insert seats (8b to e, 108b to h), excluding the first insert seat (8a, 108a), are arranged in the same axial position within the tool body (2, 102) when viewed in the longitudinal direction of the tool body (2, 102), and the first insert seat (8a, 108a) is located in the longitudinal direction of the tool body (2, 102), The tool body (2, 102) according to claim 15, characterized in that, when viewed from the rear end (4, 104) of (02) toward the front end (3, 103), it is positioned forward by at least 0.05 mm, preferably at least 0.06 mm, more preferably at least 0.07 mm, and even more preferably at least 0.07 mm, of the other insert seats (8b, e, 108b, h) of the at least three insert seats (8a, e, 108a, h).

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