Thread milling cutter and thread milling insert

Abstract

A thread milling cutter, comprising: a cutter body (2) having at least a pair of blade seats constituted by a first blade seat (10) and a second blade seat (20), the first blade seat (10) and the second blade seat (20) being angled and axially offset from each other; and a plurality of double-sided thread milling inserts (30). Each thread milling insert is adapted to the first blade seat and the second blade seat such that the thread milling insert (30): - can be mounted in the first blade seat (10) in a single working position, wherein a first set of cutting edges (40a) on a first side of the thread milling insert is in an operative cutting position, and - can be mounted in the second blade seat (20) in a single working position, wherein a second set of cutting edges (40b) on an opposite second side of the thread milling insert is in an operative cutting position. The present invention also relates to a thread milling insert suitable for use in such a thread milling cutter.

Description

Technical Field

[0001] The present invention relates to a thread milling cutter according to the preamble of claim 1. The present invention also relates to a thread milling insert for such a thread milling cutter. Background Art

[0002] A thread milling cutter is a rotary cutting tool for cutting a thread in a workpiece. The thread milling cutter may be provided with one or more cutting inserts which are detachably mounted in respective insert seats in a tool body of the thread milling cutter. These cutting inserts are hereinafter referred to as thread milling inserts. The thread milling inserts are typically provided with a plurality of teeth arranged one after another along an outer peripheral side of the thread milling insert, wherein cutting edges of the thread milling insert are formed on these teeth. Each thread milling insert is advantageously double-sided in order to increase its service life, wherein each tooth has a first cutting edge on a first side of the tooth and a corresponding second cutting edge on an opposite second side of the tooth.

[0003] A thread milling cutter with a double-sided thread milling insert has previously been known from EP 1 198 321 B1. When a cutting edge on one side of a tooth of the thread milling insert included in the thread milling cutter according to EP 1 198 321 B1 has worn off, the thread milling insert can be repositioned in its insert seat and mounted in a new inverted working position, wherein the cutting edge on the other side of the tooth is in an operative cutting position.

[0004] In the thread milling cutter disclosed in EP1 198 321B1, all the blade seats have the same axial position in the cutter body and extend side by side with each other, wherein, as seen in the longitudinal direction of the cutter body, each thread milling blade has a large number of teeth which cover the entire cutting profile of the thread milling cutter. Thus, in this case, as seen in the longitudinal direction of the cutter body, each individual thread milling blade has a rather long extension. However, as an alternative, a thread milling cutter with detachable thread milling blades may be provided with blade seats which are axially offset from each other in the longitudinal direction of the cutter body and are thus located at mutually different axial positions in the cutter body. In the latter case, as seen in the longitudinal direction of the cutter body, the cutting profile of the thread milling cutter is divided into a plurality of individual parts, wherein a first part of the cutting profile is formed by the cutting edges on the teeth of a corresponding number of first thread milling blades located in a certain number of first blade seats and positioned close to the front end of the cutter body, and a second part of the cutting profile is formed by the cutting edges on the teeth of a corresponding number of second thread milling blades located in a certain number of second blade seats and positioned further away from the front end of the cutter body. By dividing the thread milling blades into shorter blades which are axially offset from each other, the length of each individual thread milling blade can be reduced, and a more favorable distribution of the thread milling blades around the longitudinal axis of the cutter body can be achieved, which in turn enables a reduction in the vibrations induced in the cutter body by the cutting forces acting on the thread milling blades during the thread milling operation. A thread milling cutter of the last-mentioned type is disclosed, for example, in WO2010 / 101512 A2. Summary of the Invention

[0005] Object of the Invention

[0006] The object of the present invention is to provide a thread milling cutter of the above type having a new and advantageous design.

[0007] Overview of the Invention

[0008] According to the present invention, the object is achieved by a thread milling cutter having the features defined in claim 1.

[0009] The thread milling cutter according to the present invention comprises:

[0010] - an elongate cutter body having a front end and an opposite rear end, the rear end being configured for attachment to a machine such as in the form of a milling machine or a drilling machine, wherein the longitudinal axis of the cutter body extends between the rear end and the front end of the cutter body;

[0011] - At least one pair of blade seats, said at least one pair of blade seats being arranged in the tool body and consisting of a first blade seat and a second blade seat, the first blade seat and the second blade seat being angularly offset from each other about the longitudinal axis of the tool body and axially offset from each other in the longitudinal direction of the tool body, wherein the first blade seat is positioned closer to the front end of the tool body than the second blade seat, and wherein each of the first blade seat and the second blade seat has a first end and an opposite second end, and the first end of each of the first blade seat and the second blade seat is arranged to be closer to the front end of the tool body than the opposite second end of the same blade seat; and

[0012] - A plurality of geometrically identical thread milling inserts, each thread milling insert being removably mountable in a corresponding blade seat and comprising:

[0013] · An elongated insert body having a first end and an opposite second end, wherein the insert body includes a first major face and a second major face, the first major face and the second major face being arranged on opposite sides of the insert body and serving as the top face and the bottom face of the thread milling insert, and wherein the insert body is provided with an axial abutment surface at the first end of the insert body, and the axial abutment surface is configured such that when the thread milling insert is mounted in the first blade seat, the axial abutment surface abuts against a corresponding axial support surface in the first blade seat, and when the thread milling insert is mounted in the second blade seat, the axial abutment surface abuts against a corresponding axial support surface in the second blade seat, and

[0014] · A plurality of teeth, preferably three or more in number, the plurality of teeth being arranged in a row one by one along the outer peripheral side of the insert body, the outer peripheral side being located between the first major face and the second major face and extending between the first end and the second end of the insert body, wherein each tooth has a first cutting edge and a second cutting edge, the first cutting edge being on the first side of the tooth facing the first major face, the second cutting edge being on the opposite second side of the tooth facing the second major face, the first cutting edges of the teeth forming a first set of cutting edges, and the second cutting edges of the teeth forming a second set of cutting edges, wherein the first set of cutting edges and the second set of cutting edges are mirror-symmetrical with respect to an intermediate plane of the insert body, the intermediate plane extending midway between the first major face and the second major face of the insert body.

[0015] The above-described mirror symmetry of the first set of cutting edges and the second set of cutting edges means that each thread milling insert has the form of a double-sided insert having the same cutting edge profile formed on both sides of the teeth on the insert body of the thread milling insert, wherein the distance between the axial abutment surface on the thread milling insert and the proximal end of the cutting edge profile formed by the first set of cutting edges is equal within manufacturing tolerances to the distance between the axial abutment surface and the proximal end of another cutting edge profile formed by the second set of cutting edges.

[0016] The axial support surfaces in the first insert seat and the second insert seat of the at least one pair of insert seats are arranged in one of the following alternative ways:

[0017] A) The axial support surface in the first insert seat is located at the second end of the first insert seat and faces the front end of the tool body, and the axial support surface in the second insert seat is located at the first end of the second insert seat and faces the rear end of the tool body; or

[0018] B) The axial support surface in the first insert seat is located at the first end of the first insert seat and faces the rear end of the tool body, and the axial support surface in the second insert seat is located at the second end of the second insert seat and faces the front end of the tool body.

[0019] Furthermore, the thread milling inserts are adapted to the first insert seat and the second insert seat of the at least one pair of insert seats such that each thread milling insert in the thread milling inserts:

[0020] - can be mounted in the first insert seat in a single working position, wherein the axial abutment surface on the insert body of the thread milling insert abuts against the axial support surface in the first insert seat, and wherein one set of cutting edges of the first set of cutting edges and the second set of cutting edges is in the operative cutting position, i.e., in the operating position, and

[0021] - can be mounted in the second insert seat in a single working position, wherein the axial abutment surface on the insert body of the thread milling insert abuts against the axial support surface in the second insert seat, and wherein the other set of cutting edges of the first set of cutting edges and the second set of cutting edges is in the operative cutting position.

[0022] Accordingly, the thread milling inserts have the form of double-sided inserts, and each of these thread milling inserts can be mounted to the tool body in two different working positions. However, compared to conventional types of double-sided thread milling inserts, the double-sided thread milling inserts included in the thread milling tool according to the present invention are each provided with a single axial abutment surface that serves to define the axial position of the thread milling insert in the tool body in both of the two possible working positions of the thread milling insert. When the cutting edge on one side of the teeth of the thread milling insert included in the thread milling tool according to the present invention has worn away, the thread milling insert cannot be repositioned and mounted in a new inverted working position in the same insert seat. Instead, in order to bring the cutting edge on the other side of the teeth into the working cutting position, the thread milling insert must be moved from its current insert seat to another insert seat that has a different axial position in the tool body compared to the current insert seat. Thereby, incorrect mounting of individual thread milling inserts is prevented in an effective and simple manner, which in turn means that the operation for repositioning the thread milling insert can be carried out quickly and easily.

[0023] According to the present invention, in the two working positions of the thread milling insert, namely when the thread milling insert is mounted in an insert seat and the first set of cutting edges are in the operating position, and when the thread milling insert is mounted in another insert seat and the second set of cutting edges are in the operating position, one and the same surface on the thread milling insert serves as the axial abutment surface. This means that the relevant surface, i.e., the surface that serves as the axial abutment surface, can be used as an axial reference plane during the grinding of the first set of cutting edges on the first side of the teeth on the thread milling insert as well as during the grinding of the second set of cutting edges on the opposite second side of the teeth, which is advantageous with respect to the tolerances of the thread milling insert. In one grinding operation, the first set of cutting edges on the first side of the teeth on the thread milling insert and the second set of cutting edges on the opposite second side of the teeth can also be ground simultaneously, with the same axial abutment surface serving as the axial reference plane. The surface on the insert body that is opposite to the axial abutment surface does not need to be ground since it does not constitute the axial abutment surface. Accordingly, when the insert is mounted in the tool body, the tolerance of the distance between the axial abutment surface and the surface opposite to the axial abutment surface has no influence on the total tolerance of the tool. By this design of the thread milling insert, the tolerance of a thread milling tool provided with these shorter thread milling inserts mounted at two different axial positions in the tool body does not deteriorate compared to a corresponding thread milling tool provided with longer thread milling inserts, where in the corresponding thread milling tool provided with longer thread milling inserts, the teeth on each individual thread milling insert cover the entire cutting profile of the thread milling tool as seen in the longitudinal direction of the tool body.

[0024] The blade body of each thread milling blade preferably further includes a radially abutting surface, which is formed on the outer peripheral side of the blade body opposite to the toothed outer peripheral side, and the radially abutting surface is configured to abut against the corresponding radially supporting surface in either the first blade seat or the second blade seat when the thread milling blade is installed in the relevant blade seat.

[0025] According to an embodiment of the present invention, the blade body of each thread milling blade among the thread milling blades:

[0026] - is mirror-symmetrical about the intermediate plane of the blade body,

[0027] - is not mirror-symmetrical about any other plane crossing the blade body, and

[0028] - is rotationally asymmetrical about any axis crossing the blade body.

[0029] With this design of the thread milling blade, the shapes of the first blade seat and the second blade seat can be easily adapted to the shape of the thread milling blade, such that each thread milling blade can be installed only in any first blade seat positioned near the front end of the tool body in the first working position, and can be installed only in any second blade seat positioned farther from the front end of the tool body in the inverted second working position. In this context, even if any surface of the blade body is provided with one or more small marks, such as small marks in the form of depressions, and these small marks lack a mirror-symmetrical image about the intermediate plane of the blade body, the blade body is still considered mirror-symmetrical about its intermediate plane if these one or more marks are not related to the function of the thread milling blade. Furthermore, with this design of the thread milling blade, the first seat and the second seat can be given the same or at least partially the same design, which simplifies the design process of the tool body.

[0030] The shape of the blade body of each thread milling insert is preferably adapted to the shapes of the first blade seat and the second blade seat such that the blade body can be assembled into the first blade seat only when the axial abutment surface on the blade body abuts against the axial support surface in the first blade seat, i.e., it can be installed in the first blade seat, and can be assembled into the second blade seat only when the axial abutment surface on the blade body abuts against the axial support surface in the second blade seat, i.e., it can be installed in the second blade seat. For example, this can be achieved by designing the blade body of each thread milling insert in the following way: the end segment at the first end of the blade body has a shape different from the corresponding end segment at the opposite second end of the blade body. Thereby, it is possible to prevent the thread milling insert from being installed in an incorrect position in any blade seat in a simple and efficient manner. This can also be achieved by designing the blade body of each thread milling insert in the following way: the blade body includes fastening means for fastening the thread milling insert in either the first blade seat or the second blade seat, and the fastening means is arranged at different positions relative to the first end and the second end of the blade body.

[0031] The blade body of each said thread milling insert may be provided with:

[0032] - a radial abutment surface formed on the outer peripheral side of the blade body opposite to the outer peripheral side provided with the above-mentioned teeth, and the radial abutment surface is configured such that when the thread milling insert is installed in the relevant blade seat, the radial abutment surface abuts against the corresponding radial support surface in either the first blade seat or the second blade seat; and

[0033] - an inclined outer peripheral side surface forming a connection between the radial abutment surface and the first end or the second end of the blade body, and the inclined outer peripheral side surface is configured such that when the thread milling insert is installed in the relevant blade seat, it faces the corresponding inclined surface in either the first blade seat or the second blade seat.

[0034] By adapting the inclined outer peripheral side surface on the blade body of each thread milling insert to the inclined surface in the blade seat, it can be ensured that each thread milling insert can be assembled into the blade seat only in a single predetermined position where the inclined outer peripheral side surface on the blade body faces the corresponding inclined surface in any blade seat. As an alternative to the chamfered shape of the blade body formed by the inclined outer peripheral side surface and the matching chamfered shape of the blade seat formed by the corresponding inclined surface in the blade seat, the blade body and the blade seat may also have any other suitable and matching shapes.

[0035] According to another embodiment of the present invention, the axial abutment surface on the blade body of each thread milling blade among the thread milling blades is formed by an end surface at its first end on the blade body. In this case, the first blade seat can be open towards the front end surface of the tool body, that is: wherein the first end of each first blade seat is formed as an opening in the front end surface, or wherein there is a small material portion between the front end surface of the tool body and the first end of each first blade seat. In both cases, the tool is adapted to machine threads closer to the bottom of the hole in the workpiece and is better adapted to machine where it is necessary to fix the workpiece. In this case, each thread milling blade among the thread milling blades can be provided with:

[0036] - a radial abutment surface, which is formed on the outer peripheral side of the blade body opposite to the outer peripheral side provided with the above-mentioned teeth, and the radial abutment surface is configured such that when the thread milling blade is installed in the relevant blade seat, the radial abutment surface abuts against the corresponding radial support surface in any one of the first blade seat and the second blade seat; and

[0037] - an inclined outer peripheral side surface, which forms a connection portion between the axial abutment surface and the radial abutment surface on the blade body, and the inclined outer peripheral side surface is configured such that when the thread milling blade is installed in the relevant blade seat, the inclined outer peripheral side surface faces the corresponding inclined surface in any one of the first blade seat and the second blade seat.

[0038] By adapting the inclined outer peripheral side surface at the first end of the blade body of each thread milling blade to the inclined surface in the blade seat, it can be ensured that each thread milling blade is assembled into the blade seat only in a single predetermined position where the inclined outer peripheral side surface on the blade body faces the corresponding inclined surface in any blade seat. The inclined surface in the blade seat will be located at the end of each blade seat where the axial support surface of the blade seat is arranged, and compared with a blade seat having a corresponding size with a constant depth of the blade seat along the entire length of the blade seat, this end of the blade seat will thus occupy less space in the tool body, which in turn will result in an increase in the strength of the part or parts of the tool body that receive the first end of the thread milling blade. This strengthening of the tool body is particularly important if the axial support surfaces in the first blade seat and the second blade seat are arranged according to the above-mentioned alternative A and the area at the first end of each second blade seat overlaps with the area at the second end of each first blade seat (as seen in the longitudinal direction of the tool body).

[0039] As an alternative to the bevelled shape of the first end portion section of the blade body and the matching end portion section of the blade holder, these end portion sections may also have any other suitable and matching shapes.

[0040] The first blade holder and the second blade holder in the at least one pair of blade holders may have axial positions relative to each other in the tool body such that: the axial distance between the tooth on the thread milling blade mounted in the first blade holder closest to the second end of the first blade holder and the tooth on the thread milling blade mounted in the second blade holder closest to the first end of the second blade holder is substantially equal to the axial distance between two adjacent teeth on any one of the helical milling blades in these thread milling blades. However, as an alternative, the first blade holder and the second blade holder in the at least one pair of blade holders may have axial positions relative to each other in the tool body such that: the tooth on the thread milling blade mounted in the first blade holder closest to the second end of the first blade holder and the tooth on the thread milling blade mounted in the second blade holder closest to the first end of the second blade holder are located at the same axial position in the tool body, and thus overlap each other in the longitudinal direction of the tool body.

[0041] According to another embodiment of the present invention, two or more pairs of such blade holders are provided in the tool body, wherein the first blade holders in different pairs of blade holders are located at the same axial position in the tool body and are evenly distributed around the longitudinal axis of the tool body, and wherein the second blade holders in different pairs of blade holders are located at the same axial position in the tool body and are evenly distributed around the longitudinal axis of the tool body.

[0042] Further advantageous features of the thread milling tool according to the present invention will become apparent from the following description.

[0043] The present invention also relates to a thread milling blade for a thread milling tool of the above type.

[0044] The thread milling blade according to the present invention comprises:

[0045] - An elongated blade body having a first end and an opposite second end, wherein the blade body includes a first major face and a second major face, the first major face and the second major face being disposed on opposite sides of the blade body and serving as the top face and the bottom face of the thread milling insert, and wherein the blade body is provided with an axial abutment surface at the first end of the blade body, and the axial abutment surface is configured to abut against a corresponding axial support surface in a blade seat of the thread milling cutter when the thread milling insert is mounted in the blade seat; and

[0046] - A plurality of teeth arranged in rows one after another along the outer peripheral side of the blade body, the outer peripheral side being located between the first major face and the second major face and extending between the first end and the second end of the blade body, each tooth having a first cutting edge and a second cutting edge, wherein the first cutting edge is on a first side of the tooth facing the first major face, the second cutting edge is on a second opposite side of the tooth facing the second major face, and wherein the first cutting edge and the second cutting edge on each tooth are mirror-symmetrical to each other with respect to a middle plane of the blade body, the middle plane extending in the middle between the first major face and the second major face of the blade body.

[0047] The blade body:

[0048] - Is mirror-symmetrical with respect to the middle plane of the blade body,

[0049] - Is not mirror-symmetrical with respect to any other plane crossing the blade body, and

[0050] - Is not rotationally symmetrical with respect to any axis crossing the blade body.

[0051] The above-mentioned mirror symmetry of the cutting edge and the blade body means that the thread milling blade has the form of a double-sided blade with the same cutting edge profile formed on both sides of the teeth formed on the blade body, where the distance between the axial abutment surface and the proximal end of the cutting edge profile on the first side of the tooth is equal within the manufacturing tolerance to the distance between the abutment surface and the proximal end of the other cutting edge profile on the opposite second side of the tooth. In addition, the above-mentioned mirror asymmetry and rotational asymmetry of the blade body mean that the blade seat of the thread milling cutter can be easily adapted to the shape of the blade body such that the thread milling blade can be mounted in a single predetermined working position in each blade seat. Therefore, the thread milling blade with a blade body of this design is suitable for use in a thread milling cutter of the above type. In this context, even if any surface of the blade body is provided with one or more small markings, such as small markings in the form of depressions, which lack a mirror-symmetrical image with respect to the intermediate plane of the blade body, the blade body is still considered to be mirror-symmetrical with respect to its intermediate plane if these one or more markings are not relevant to the function of the thread milling blade.

[0052] Further advantageous features of the thread milling blade according to the invention will become apparent from the dependent claims and the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] With reference to the accompanying drawings, a specific description of embodiments of the invention cited as examples follows. In the drawings:

[0054] Figure 1 and Figure 2 is a perspective view of a thread milling cutter according to a first embodiment of the invention,

[0055] Figure 3 and Figure 4 is Figure 1 and Figure 2 perspective views of a part of the thread milling cutter viewed from different directions,

[0056] Figure 5 is Figure 1 and Figure 2 side views of the thread milling cutter,

[0057] Figure 6 is Figure 1 and Figure 2 front views of the thread milling cutter,

[0058] Figure 7 is a sectional view taken along line A-A in Figure 6 and

[0059] Figure 8 is a sectional view taken along line B-B in Figure 6 and

[0060] Figures 9a and 9b are Figure 1 and Figure 2 perspective views of a thread milling insert included in a thread milling cutter, as viewed from different directions,

[0061] Figure 10 is a rear view of the thread milling insert of Figures 9a and 9b,

[0062] Figure 11 and Figure 12 are perspective views of a thread milling cutter according to a second embodiment of the present invention,

[0063] Figure 13 and Figure 14 are Figure 11 and Figure 12 perspective views of a part of a thread milling cutter, as viewed from different directions,

[0064] Figure 15 are Figure 11 and Figure 12 side views of a thread milling cutter,

[0065] Figure 16 are Figure 11 and Figure 12 front views of a thread milling cutter,

[0066] Figure 17 is a sectional view taken along line C-C in Figure 16 ,

[0067] Figure 18 is a sectional view taken along line D-D in Figure 16 ,

[0068] Figures 19a and 19b are Figure 11 and Figure 12 perspective views of a thread milling insert included in a thread milling cutter, as viewed from different directions,

[0069] Figure 20 is a rear view of the thread milling insert of Figures 19a and 19b, and

[0070] Figure 21 is a side view of a thread milling insert of an alternative variant. Detailed Description

[0071] Figures 1 to 8 and Figures 11 to 18Two different embodiments of a thread milling cutter 1 according to the present invention are shown. The thread milling cutter 1 includes an elongate cutter body 2 and is configured to rotate about a rotational axis 3. The cutter body 2 has a front end 2a and an opposite rear end 2b. A longitudinal axis 4 of the cutter body 2 extends between the rear end 2b and the front end 2a of the cutter body, wherein the longitudinal axis 4 coincides with the rotational axis 3 of the thread milling cutter 1. In the illustrated embodiment, a collar 5 is provided at the middle of the cutter body. A rear portion of the cutter body located between the collar 5 and the rear end 2b forms a connection member 6 through which the cutter body 2 can be mounted directly or via an intermediate tool holder to a selected spindle or a similar component of a machine (e.g., a milling machine or a drilling machine). A front portion of the cutter body 2 located between the collar 5 and the front end 2a is provided with blade seats 10, 20 which are configured to receive thread milling inserts 30. The blade seats 10, 20 are arranged in pairs, wherein each pair includes a first blade seat 10 positioned closer to the front end 2a of the cutter body 2 and a second blade seat 20 positioned further away from the front end 2a of the cutter body 2. Thus, the first blade seat 10 and the second blade seat 20 are axially offset from each other in the longitudinal direction of the cutter body 2, wherein the first blade seat 10 is positioned closer to the front end 2a of the cutter body 2 than the second blade seat 20. In addition, the first blade seat 10 and the second blade seat 20 are angularly offset from each other with respect to the longitudinal axis 4 of the cutter body 2. The first blade seat 10 extends in the longitudinal direction of the cutter body 2 and has a first end 10a and an opposite second end 10b, wherein the first end 10a of the first blade seat is closer to the front end 2a of the cutter body 2 than the second end 10b of the first blade seat. Moreover, the second blade seat 20 extends parallel to the first blade seat 10 in the longitudinal direction of the cutter body 2 and has a first end 20a and an opposite second end 20b, wherein the first end 20a of the second blade seat is closer to the front end 2a of the cutter body 2 than the second end 20b of the second blade seat.

[0072] In Figures 1 to 8 the illustrated embodiment, the cutter body 2 is provided with two pairs of blade seats 10, 20 of the above type. In Figures 11 to 18In the illustrated embodiment, the tool body 2 is provided with three pairs of blade seats 10, 20 of the above type. However, as an alternative, the tool body 2 can be provided with any other suitable number of blade seats, especially depending on the diameter of the tool body. A tool body with a smaller diameter can, for example, be provided with only one pair of blade seats 10, 20, while a tool body with a larger diameter can be provided with more than three pairs of blade seats 10, 20. When the tool body 2 is provided with two or more pairs of blade seats, the first blade seats 10 in different pairs are located at the same axial position in the tool body 2 and are evenly distributed around the longitudinal axis 4 of the tool body. In a corresponding manner, the second blade seats 20 in different pairs are located at the same axial position in the tool body 2 and are evenly distributed around the longitudinal axis 4 of the tool body. In addition, as seen in the circumferential direction of the tool body 2, the first blade seats 10 and the second blade seats 20 are arranged alternately. Thus, when viewed in the circumferential direction of the tool body 2, each first blade seat 10 is arranged between two second blade seats 20, and each second blade seat 20 is arranged between two first blade seats.

[0073] Each blade seat 10, 20 is configured to receive a thread milling insert 30. The thread milling inserts 30 received in the first blade seats 10 and the second blade seats 20 are identical to each other in geometry, or at least substantially identical to each other in geometry. Thus, the thread milling inserts 30 included in the same thread milling tool 1 all have the same basic shape and the same dimensions. The thread milling insert 30 has the form of a double-sided insert and can be detachably mounted in the blade seats 10, 20.

[0074] Each thread milling insert 30 includes an elongate insert body 31 having a first end 31a and an opposite second end 31b. The insert body 31 includes a first major face 32 and a second major face 33 which are disposed on opposite sides of the insert body 31 and serve as the top and bottom faces of the thread milling insert 30. The first major face 32 and the second major face 33 of the insert body 31 extend between the first end 31a and the second end 31b of the insert body 31. An intermediate plane MP which constitutes an imaginary plane extends intermediate between the first major face 32 and the second major face 33 of the insert body 31, as shown in FIGS. 10 and 20. Each thread milling insert 30 further includes a plurality of teeth 34 which are arranged in a row one after another along the outer peripheral side 35 of the insert body 31, the outer peripheral side 35 being located between the first major face 32 and the second major face 33 and extending between the first end 31a and the second end 31b of the insert body 31. Each tooth 34 has a first side surface 37, an opposite second side surface 38 and an outer peripheral surface 39 which extends between the first side surface 37 and the second side surface 38. On each tooth, a first cutting edge 40a is formed at the intersection between the outer peripheral surface 39 and the first side surface 37, and a second cutting edge 40b is formed at the intersection between the outer peripheral surface 39 and the second side surface 38. The first cutting edge 40a is disposed on the first side of the tooth 34 facing the first major face 32 of the insert body 31, and the second cutting edge 40b is disposed on the opposite second side of the tooth 34 facing the second major face 33 of the insert body 31. The first cutting edge 40a and the second cutting edge 40b may extend respectively along the entire or substantially the entire intersection line between the outer peripheral surface 39 and the first side surface 37 and the second side surface 38, or at least along a part thereof at the tip of the tooth 34. In the latter case, each of the first cutting edge 40a and the second cutting edge 40b terminates at a distance from the base of the tooth 34 on either side of the tip of the tooth. The first side surface 37 is configured to serve as the rake face of the first cutting edge 40a, and the second side surface 38 is configured to serve as the rake face of the second cutting edge 40b. The outer peripheral surface 39 serves as the clearance surface of the first cutting edge 40a and the second cutting edge 40b and extends perpendicular to the intermediate plane MP, as shown in FIGS. 10 and 20.

[0075] In the illustrated embodiment, the first side surface 37 and the second side surface 38 of each tooth 34 are inclined outwardly at an acute angle α with respect to each other, as seen in the direction from the base of the tooth towards the tip of the tooth, as shown in FIGS. 10 and 20.

[0076] On each individual thread milling insert 30, the first cutting edge 40a of the teeth 34 forms a first set of cutting edges of the thread milling insert, and the second cutting edge 40b of the teeth 34 forms a second set of cutting edges of the thread milling insert. The first set of cutting edges 40a and the second set of cutting edges 40b are mirror-symmetrical to each other with respect to the intermediate plane MP of the insert body 31.

[0077] In Figure 1 to Figure 1 the embodiment shown in Figures 11 to 2 0, each thread milling insert 31 is provided with three teeth 34, while in

[0078] the embodiment shown in 0, each thread milling insert 31 is provided with seven teeth 34. However, the thread milling insert 31 may be provided with any other suitable number of teeth 34.

[0079] The blade body 31 of each thread milling insert 30 is provided with an axial abutment surface 41 at a first end 31a of the blade body 31, and the axial abutment surface 41 is configured such that when the thread milling insert 30 is mounted in a relevant first blade seat, the axial abutment surface 41 abuts against a corresponding axial support surface 11 in any one of the first blade seats 10, and when the thread milling insert 30 is mounted in a relevant second blade seat, the axial abutment surface 41 abuts against a corresponding axial support surface 21 in any one of the second blade seats 20. Accordingly, each blade seat 10, 20 is provided with axial support surfaces 11, 21 which are configured to engage with the axial abutment surface 41 on the blade body 31 of the thread milling insert 30 when the thread milling insert 30 is mounted in the blade seats 10, 20. In the illustrated embodiment, the axial support surface 11 in each first blade seat 10 is located at a second end 10b of the first blade seat and faces the front end 2a of the tool body 2, while the axial support surface 21 of each second blade seat 20 is located at a first end 20a of the second blade seat and faces the rear end 2b of the tool body 2. In this case, the first blade seats 10 can be open towards the front surface 7 of the tool body 2, i.e., the first end 10a of each first blade seat 10 is formed as an opening in the front surface 7. In an alternative embodiment (not shown), the axial support surface 11 in each first blade seat 10 is located at a first end 10a of the first blade seat and faces the rear end 2b of the tool body 2, while the axial support surface 21 in each second blade seat 20 is located at a second end 20b of the second blade seat and faces the front end 2a of the tool body 2.

[0080] In the illustrated embodiment, the axial abutment surface 41 on the blade body 31 of each thread milling insert 30 is formed by an end surface on the blade body 31 at its first end 31a. The axial abutment surface 41 is preferably a planar surface extending perpendicular to the intermediate plane MP of the blade body 31, wherein the axial support surfaces 11, 21 in each blade seat 10, 20 are planar surfaces extending perpendicular to the longitudinal axis 4 of the tool body 2. However, the axial abutment surface 41 and the axial support surfaces 11, 21 can also have any other suitable and mutually matching shapes.

[0081] The blade body 31 of each thread milling blade 30 is further provided with a radially abutting surface 43, which is formed on the outer peripheral side 45 of the blade body opposite to the outer peripheral side 35 provided with teeth 34, wherein the radially abutting surface 43 is configured such that when the thread milling blade 30 is installed in the relevant first blade seat, the radially abutting surface 43 abuts against the corresponding radially supporting surface 13 in any first blade seat 10, and when the thread milling blade 30 is installed in the relevant second blade seat, the radially abutting surface 43 abuts against the corresponding radially supporting surface 23 in any second blade seat 20. Preferably, the radially abutting surface 43 is perpendicular to the axially abutting surface 41. Thus, each blade seat 10, 20 is provided with radially supporting surfaces 13, 23, which are configured to engage with the radially abutting surface 43 on the blade body 31 of the thread milling blade 30 when the thread milling blade 30 is installed in the blade seats 10, 20. Preferably, the radially supporting surfaces 13, 23 are perpendicular to the axially supporting surfaces 11, 21.

[0082] In the illustrated embodiment, each thread milling blade 30 is configured to be releasably fixed to either of the blade seats 10, 20 in the tool body 2 by two fastening elements 8 in the form of screws, the two fastening elements 8 extending through a respective one of the through holes 42 in the blade body 31 of the thread milling blade and engaging in threaded holes 12, 22 in the tangentially supporting surfaces 14, 24 in the blade seats (see Figures 2 to 4 and Figures 12 to 14 ). Each fastening element 8 includes an elongate shaft 8a and a head 8b, wherein the elongate shaft 8a is provided with an external thread configured to engage with the corresponding internal thread in either of the threaded holes 12, 22, and the head 8b is fixed to the shaft 8a. The outer diameter of the shaft 8a is smaller than the inner diameter of the through hole 42 in the blade body 31 such that the shaft 8a can be received in either of the through holes 42 with play, as shown in Figure 7 , Figure 8 , Figure 17 and Figure 18 . Each through hole 42 is provided with a tapered inner surface 42a at each of its ends, which is configured to engage with the corresponding tapered outer surface 8c on the head 8b of each fastening element. When the fastening element 8 is screwed into one of the threaded holes 12, 22 in either of the blade seats 10, 20 and the shaft 8a of the fastening element 8 is received in one of the through holes 42 in the blade body 31 of the thread milling blade 30 positioned in the relevant blade seat, the tapered outer surface 8c on the head 8b will engage with one of the tapered inner surfaces 42a in the through hole 42 and thereby push the blade body 31 against the axially supporting surfaces 11, 21 in the blade seat.

[0083] According to the present invention, a thread milling insert 30 is adapted to a first insert seat 10 and a second insert seat 20 such that each thread milling insert 30:

[0084] - can be mounted in any one of the first insert seats in the first insert seat 10 in a single working position, wherein an axial abutment surface 41 on the insert body 31 of the thread milling insert abuts against an axial support surface 11 in the relevant first insert seat 10, and wherein one of a first set of cutting edges 40a and a second set of cutting edges 40b is in an operative cutting position, and

[0085] - can be mounted in any one of the second insert seats in the second insert seat 20 in a single working position, wherein an axial abutment surface 41 on the insert body 31 of the thread milling insert abuts against an axial support surface 21 in the relevant second insert seat 20, and wherein the other of the first set of cutting edges 40a and the second set of cutting edges 40b is in an operative cutting position.

[0086] In the illustrated embodiment:

[0087] - When the thread milling insert is mounted in one of the first insert seats in the first insert seat 10, the first set of cutting edges 40a of the thread milling insert 30 is always in an operative cutting position, wherein a second major surface 33 of the insert body 31 or at least a part thereof abuts against a tangential support surface 13 in the relevant insert seat 10; and

[0088] - When the thread milling insert is mounted in one of the second insert seats in the second insert seat 20, the second set of cutting edges 40b of the thread milling insert 30 is always in an operative cutting position, wherein a first major surface 32 of the insert body 31 or at least a part thereof abuts against a tangential support surface 23 in the relevant insert seat 20.

[0089] In Figures 1 to 2 the illustrated embodiment, the shape of the insert body 31 of each thread milling insert 30 is adapted to the shapes of the first insert seat 10 and the second insert seat 20 such that the insert body 31 is assembled into any first insert seat 10 only in a position where the axial abutment surface 41 on the insert body 31 abuts against the axial support surface 11 in the first insert seat 10, and is assembled into any second insert seat 20 only in a position where the axial abutment surface 41 on the insert body 31 abuts against the axial support surface 21 in the second insert seat 20.

[0090] In Figures 1 to 2In the embodiment shown in 0, the blade body 31 of each thread milling blade 30 has a first end portion section 46a at its first end 31a, and the shape of the first end portion section 46a is different from the shape of the corresponding second end portion section 46b at the opposite second end 31b of the blade body. To ensure that the thread milling blade 30 is correctly installed in the blade seats 10, 20, each of the first blade seat 10 and the second blade seat 20 has a first end portion section 16a, 26a (see Figure 3 , Figure 4 , Figure 13 and Figure 14 ) at one of its ends 10b, 20a, and the first end portion section has a shape adapted to the shape of the first end portion section 46a of the blade body 31 of each thread milling blade 30, and each blade seat has a second end portion section 16b, 26b with a different shape at the other end 10a, 20b (see Figure 3 , Figure 4 , Figure 13 and Figure 14 ), and the second end portion section has a shape adapted to the shape of the second end portion section 46b of the blade body 31 of each thread milling blade 30.

[0091] In the embodiment shown in Figures 1 to 2 0, the above-mentioned first end portion section 46a of the blade body 31 includes an inclined outer peripheral side surface 47, and the inclined outer peripheral side surface 47 forms a connecting portion between the axial abutting surface 41 and the radial abutting surface 43 on the blade body 31, and the inclined outer peripheral side surface 47 is configured to face the corresponding inclined surfaces 17, 27 at the first end portion sections 16a, 26a of any one of the first blade seat 10 and the second blade seat 20 when the thread milling blade 30 is installed in the relevant blade seat. The opposite second end portion section 46b of the blade body 31 does not have such an inclined outer peripheral side surface, thereby preventing the second end portion section 46b of the blade body 31 from being assembled into the first end portion sections 16a, 26a of any one of the first blade seat 10 and the second blade seat 20. The above-mentioned inclined surfaces 17 and 27 form corresponding chamfered corners at the first end portion sections 16a, 26a of the first blade seat 10 and the second blade seat 20, and the chamfered corners together with the non-inclined second end portion section 46b of the blade body 31 will prevent the thread milling blade 31 from being installed in any one of the blade seats 10, 20 when the second end 31b of the blade body faces the axial support surfaces 11, 21 in the blade seat.

[0092] In the embodiment shown in FIG. 21, the first end 31a and the second end 31b of the blade body 31 of the thread milling blade 30 have the same shape. In this case, compared with Figures 1 to 2As compared to the symmetric arrangement of the through holes 42 in the blade body 31 in the embodiment shown in FIG. 0, the position of the through holes 42 in the blade body 31 has moved towards the second end 31b of the blade body. In the embodiment shown in FIG. 21, the asymmetric arrangement of the through holes 42 in the blade body 31 and the corresponding arrangement of the threaded holes 12, 22 in the blade holders 10, 20 ensure that the thread milling blade 30 can only be mounted in a single working position in each of the blade holders 10, 20.

[0093] In the illustrated embodiment, the blade body 31 of each thread milling blade 30:

[0094] - is mirror-symmetric about the middle plane MP of the blade body 31,

[0095] - is mirror-asymmetric about any other plane passing through the blade body 31, and

[0096] - is rotation-asymmetric about any axis passing through the blade body 31.

[0097] Thus, in this case, the first major face 32 and the second major face 33 of the blade body 31 are identical to each other within the manufacturing tolerances and are mirror-symmetric about the middle plane MP of the blade body 31.

[0098] In Figures 1 to 8 the illustrated embodiment, the first blade holder 10 and the second blade holder 20 have such an axial position relative to each other in the tool body 2 that: the axial distance between the tooth 34 on the thread milling blade 30 closest to the second end 10b of the first blade holder 10 mounted in any one of the first blade holders 10 and the tooth 34 on the thread milling blade 30 closest to the first end 20a of the adjacent second blade holder 20 is substantially equal to the axial distance between two adjacent teeth 34 on any one of these thread milling blades.

[0099] In Figures 11 to 18 the illustrated embodiment, the first blade holder 10 and the second blade holder 20 have such an axial position relative to each other in the tool body 2 that: the tooth 34 on the thread milling blade 30 closest to the second end 10b of the first blade holder 10 mounted in any one of the first blade holders 10 and the tooth 34 on the thread milling blade 30 closest to the first end 20a of the adjacent second blade holder 20 are located at the same axial position in the tool body 2 and thus overlap each other as seen in the longitudinal direction of the tool body 2.

[0100] Of course, the present invention is not limited in any way to the above embodiments. On the contrary, many possibilities for modifying the present invention will be obvious to those of ordinary skill in the art without departing from the basic idea of the present invention as defined in the appended claims.

Claims

1. A thread milling cutter, comprising: - An elongated cutter body (2), the cutter body (2) having a front end (2a) and an opposite rear end (2b), the rear end (2b) being configured for attachment to a machine, wherein a longitudinal axis (4) of the cutter body (2) extends between the rear end (2b) and the front end (2a) of the cutter body; - At least a pair of blade seats (10, 20), the at least a pair of blade seats (10, 20) being provided in the cutter body (2) and consisting of a first blade seat (10) and a second blade seat (20), the first blade seat (10) and the second blade seat (20) being angularly offset from each other with respect to the longitudinal axis (4) of the cutter body (2) and axially offset from each other in the longitudinal direction of the cutter body (2), wherein the first blade seat (10) is positioned closer to the front end (2a) of the cutter body (2) than the second blade seat (20), wherein each of the first blade seat (10) and the second blade seat (20) has a first end (10a, 20a) and an opposite second end (10b, 20b), and the first end (10a, 20a) of each of the first blade seat (10) and the second blade seat (20) is arranged closer to the front end (2a) of the cutter body (2) than the opposite second end (10b, 20b) of the same blade seat; And - A plurality of thread milling blades (30) that are substantially identical in geometry, each thread milling blade being removably mountable in a corresponding one of the at least a pair of blade seats (10, 20), and each thread milling blade comprising: · An elongated blade body (31), the elongated blade body (31) having a first end (31a) and an opposite second end (31b), wherein the blade body (31) comprises a first major surface (32) and a second major surface (33), the first major surface (32) and the second major surface (33) being arranged on opposite sides of the blade body and serving as the top surface and the bottom surface of the thread milling blade, and wherein the blade body (31) is provided with an axial abutment surface (41) at the first end (31a) of the blade body (31), the axial abutment surface (41) being configured such that when the thread milling blade (30) is mounted in the first blade seat (10), the axial abutment surface (41) abuts against a corresponding axial support surface (11) in the first blade seat (10), and when the thread milling blade (30) is mounted in the second blade seat, the axial abutment surface (41) abuts against a corresponding axial support surface (21) in the second blade seat (20), and · A plurality of teeth (34) are arranged in a row one by one along the outer peripheral side (35) of the blade body (31). The outer peripheral side (35) is located between the first main surface (32) and the second main surface (33), and extends between the first end (31a) and the second end (31b) of the blade body (31). Each tooth (34) of the plurality of teeth (34) has a first cutting edge (40a) and a second cutting edge (40b). The first cutting edge (40a) is on the first side of the tooth facing the first main surface (32), and the second cutting edge (40b) is on the opposite second side of the tooth facing the second main surface (33). The first cutting edges (40a) of the plurality of teeth (34) form a first set of cutting edges, and the second cutting edges (40b) of the plurality of teeth (34) form a second set of cutting edges. The first set of cutting edges (40a) and the second set of cutting edges (40b) are mirror-symmetrical to each other with respect to the intermediate plane (MP) of the blade body (31), and the intermediate plane (MP) extends in the middle between the first main surface (32) and the second main surface (33) of the blade body (31). It is characterized in that: - The axial support surfaces (11) of the first blade seat (10) and the axial support surfaces (21) of the second blade seat (20) in the at least one pair of blade seats are arranged such that: · The axial support surface (11) in the first blade seat (10) is located at the second end (10b) of the first blade seat and faces the front end (2a) of the tool body (2), and the axial support surface (21) in the second blade seat (20) is located at the first end (20a) of the second blade seat, and faces the rear end (2b) of the tool body (2), or · The axial support surface (11) in the first blade seat (10) is located at the first end (10a) of the first blade seat and faces the rear end (2b) of the tool body (2), and the axial support surface (21) in the second blade seat (20) is located at the second end (20b) of the second blade seat, and faces the front end (2a) of the tool body (2); and - Each thread milling blade (30) in the thread milling blades is adapted to the first blade seat (10) and the second blade seat (20) of the at least one pair of blade seats, such that the thread milling blade (30): · Can be installed in the first blade seat (10) in a single working position, wherein the axial abutment surface (41) on the blade body (31) of the thread milling insert abuts against the axial support surface (11) in the first blade seat (10), and wherein one of the first set of cutting edges (40a) and the second set of cutting edges (40b) is in an operative cutting position, and · can be mounted in the second blade seat (20) in a single working position, wherein the axial abutment surface (41) on the blade body (31) of the thread milling insert abuts against the axial support surface (21) in the second blade seat (20), and wherein the other of the first set of cutting edges (40a) and the second set of cutting edges (40b) is in an operative cutting position.

2. The thread milling cutter according to claim 1, characterized in that, The blade body (31) of each said thread milling insert: - is mirror-symmetrical about the median plane (MP) of the blade body (31), - is not mirror-symmetrical about any other plane transverse to the blade body (31), and - is not rotationally symmetrical about any axis transverse to the blade body (31).

3. The thread milling cutter according to claim 1 or 2, characterized in that, The shape of the blade body (31) of each thread milling insert (30) in the thread milling inserts is adapted to the shape of the first blade seat (10) and the second blade seat (20) in the at least one pair of blade seats such that the blade body (31) is assembled into the first blade seat (10) only in a position where the axial abutment surface (41) on the blade body (31) abuts against the axial support surface (11) in the first blade seat (10), and is assembled into the second blade seat (20) only in a position where the axial abutment surface (41) on the blade body (31) abuts against the axial support surface (21) in the second blade seat (20).

4. The thread milling cutter according to claim 3, characterized in that, The shape of the end segment (46a) at the first end (31a) of the blade body (31) of each thread milling insert (30) in the thread milling inserts is different from the shape of the corresponding end segment (46b) at the second end (31b) of the blade body (31).

5. The thread milling cutter according to any one of claims 1-4, characterized in that, The axial abutment surface (41) on the blade body (31) of each thread milling insert (30) in the thread milling inserts is formed by an end surface on the blade body (31) at the first end (31a) of the blade body (31).

6. The thread milling cutter according to claim 5, characterized in that, The blade body (31) of each thread milling insert (30) in the thread milling inserts is provided with: - a radially abutting surface (43) which is formed on the outer peripheral side (45) of the blade body opposite to the outer peripheral side (35) provided with the teeth (34), and the radially abutting surface (43) is configured such that when the thread milling blade (30) is mounted in the relevant blade seat, the radially abutting surface (43) abuts against the corresponding radial support surface (13, 23) in either the first blade seat (10) or the second blade seat (20); and - an inclined outer peripheral side surface (47) which forms a connection portion between the axial abutting surface (41) and the radially abutting surface (43) on the blade body (31), and the inclined outer peripheral side surface (47) is configured such that when the thread milling blade (30) is mounted in the relevant blade seat, the inclined outer peripheral side surface (47) faces the corresponding inclined surface (17, 27) in either the first blade seat (10) or the second blade seat (20).

7. The thread milling cutter according to any one of claims 1-6, characterized in that, The number of the plurality of teeth (34) is at least three.

8. The thread milling cutter according to any one of claims 1-7, characterized in that, The first blade seat (10) and the second blade seat (20) in the at least one pair of blade seats have such an axial position relative to each other in the tool body (2) that the axial distance between the tooth (34) on the thread milling blade (30) mounted in the first blade seat (10) closest to the second end (10b) of the first blade seat (10) and the tooth (34) on the thread milling blade (30) mounted in the second blade seat (20) closest to the first end (20a) of the second blade seat (20) is substantially equal to the axial distance between two adjacent teeth (34) on any one of these thread milling blades.

9. The thread milling cutter according to any one of claims 1-7, characterized in that, The first blade seat (10) and the second blade seat (20) in the at least one pair of blade seats have such an axial position relative to each other in the tool body (2) that the tooth (34) on the thread milling blade (30) mounted in the first blade seat (10) closest to the second end (10b) of the first blade seat (10) and the tooth (34) on the thread milling blade (30) mounted in the second blade seat (20) closest to the first end (20a) of the second blade seat (20) are located at the same axial position in the tool body (2) and thus overlap each other in the longitudinal direction of the tool body.

10. The thread milling cutter according to any one of claims 1-9, characterized in that, In the tool body (2), there are provided two or more pairs of such blade seats (10, 20), wherein the first blade seats (10) in different pairs of blade seats are located at the same axial position in the tool body (2) and are evenly distributed around the longitudinal axis (4) of the tool body, and wherein the second blade seats (20) in different pairs of blade seats are located at the same axial position in the tool body (2) and are evenly distributed around the longitudinal axis (4) of the tool body.

11. A thread milling insert for a thread milling tool, the thread milling insert (30) comprising: - an elongate insert body (31) having a first end (31a) and an opposite second end (31b), wherein the insert body (31) includes a first major face (32) and a second major face (33), the first major face (32) and the second major face (33) being arranged on opposite sides of the insert body and serving as the top face and the bottom face of the thread milling insert, and wherein the insert body (31) is provided with an axial abutment surface (41) at the first end (31a) of the insert body (31), and the axial abutment surface (41) is configured such that when the thread milling insert (30) is mounted in a blade seat, the axial abutment surface (41) abuts against a corresponding axial support surface (11, 21) in the blade seat (10, 20) in the thread milling tool; and - a plurality of teeth (34) arranged in rows one after another along the outer peripheral side (35) of the insert body (31), the outer peripheral side (35) being located between the first major face (32) and the second major face (33) and extending between the first end (31a) and the second end (31b) of the insert body (31), each tooth (34) having a first cutting edge (40a) and a second cutting edge (40b), the first cutting edge (40a) being on the first side of the tooth facing the first major face (32), the second cutting edge (40b) being on the opposite second side of the tooth facing the second major face (33), wherein the first cutting edge (40a) and the second cutting edge (40b) on each tooth (34) are mirror-symmetrical to each other with respect to a middle plane (MP) of the insert body (31), the middle plane (MP) extending in the middle between the first major face (32) and the second major face (33) of the insert body, characterized in that the insert body (31): - is mirror-symmetrical with respect to the middle plane (MP) of the insert body (31), - is not mirror-symmetrical with respect to any other plane crossing the insert body (31), and - is not rotationally symmetrical with respect to any axis crossing the insert body (31).

12. The thread milling insert according to claim 11, wherein, The shape of the end section (46a) of the blade body (31) at the first end (31a) of the blade body (31) is different from the shape of the corresponding end section (46b) at the second end (31b) of the blade body.

13. The thread milling insert according to claim 11 or 12, characterized in that, The axial abutment surface (41) on the blade body (31) is formed by an end surface on the blade body (31) at the first end (31a) of the blade body (31).

14. The thread milling insert according to claim 13, wherein, The blade body (31) is provided with: - a radial abutment surface (43) formed on the outer peripheral side (45) of the blade body opposite to the outer peripheral side (35) provided with the teeth (34), and the radial abutment surface (43) is configured such that when the thread milling blade (30) is mounted in the blade seats (10, 20) in the thread milling cutter, the radial abutment surface (43) abuts against the corresponding radial support surfaces (13, 23) in the blade seats (10, 20); and - an inclined outer peripheral side surface (47) forming a connection portion between the axial abutment surface (41) and the radial abutment surface (43) on the blade body (31).

15. The thread milling insert according to any one of claims 11-14, characterized in that, The number of the plurality of teeth (34) is at least three.

Images