JP2501853Y2 - Throwaway Face Milling - Google Patents

Description

[Detailed Description of the Invention] "Industrial application field" The present invention is capable of smoothly performing not only flat surface cutting but also recess processing, etc., and further improves the economical efficiency of the throwaway chip. Regarding the face milling machine.

"Prior art" Fig. 16 shows a square plate-shaped throwaway tip (hereinafter,
1 shows an example of a general throwaway type front milling cutter (hereinafter simply referred to as front milling cutter) to which a tip is abbreviatedly attached, and reference numeral 1 in the drawing denotes a tool body. The tool main body 1 is attached to a main shaft of a milling machine or the like, and is composed of a cylindrical mounting portion 2 that rotates around a rotation axis O, and a head 3 formed at the tip of the mounting portion 2. The head 3 has a thick disc shape, and a tip 4 having a quadrangular plate shape is detachably attached to the outer peripheral portion of the tip thereof.

The main cutting edge 5 of the chip 4 is inclined 45 ° with respect to the rotation axis O so as to gradually approach the rotation axis O of the tool body 1 as it goes toward the tip side of the tool body 1, and a so-called corner angle is 45 degrees. It is said to be °.

"Problems to be solved by the invention" By the way, when performing surface cutting with the above face milling machine, constraints such as power of the machine used such as a milling machine, hardness of the work material, and distortion of the work material due to cutting heat for,
At present, only about 1/2 to 1/3 of the total length of the main cutting edge 5 can be used. Therefore, there is a problem that the main cutting edge 5 of the used chip 4 to be discarded has an unused portion, which is very uneconomical.

Further, even if the above restriction can be eliminated, there is a problem that when the cutting is performed with the entire length of the main cutting edge 5, the end of the main cutting edge 5 is likely to be chipped.

By the way, as the chip used for the cutting process, in addition to the rectangular flat plate-shaped chip as described above, for example, Japanese Patent Laid-Open No.
There is an octagonal flat plate-like one as described in JP-A-65578. However, in this publication, regarding such an octagonal tip, it is only described that it is used for a turning tool such as a cutting tool, and mounting on a face mill such as described above is described. No, not even suggesting how the most efficient use of the tip can be achieved in a face mill.

Therefore, the present invention was made in order to solve the above-mentioned problems by using such an octagonal tip, and the entire length thereof can be used without causing a chip in the cutting edge. The aim is to provide a face mill that can be used very economically.

"Means for Solving the Problem" The front milling cutter of the present invention is a front face in which a tip mounting seat is provided on the outer peripheral portion of the tip of a tool body that rotates around a rotation axis, and a tip is detachably mounted on each tip mounting seat. In the milling cutter, the above-mentioned tip is a substantially regular octagonal plate-shaped positive tip, and a cutting edge is formed on each ridge line portion of one side forming a regular octagon that is a rake face, and this one side is a tool. One of the cutting blades is located on the outer peripheral side of the tip of the tool body toward the rotational direction side so as to incline toward the inner peripheral side toward the tip side, and also the one of the cutting blades. The other cutting edge located adjacent to the base end side on the outer peripheral side of the tool is substantially parallel to the rotation axis when viewed from the tool rotation direction side, and the one cutting edge and the one cutting edge. The cutting edge that is located on the inner peripheral side of the , Around the rotation axis with the cutting edge that is continuous to the inner peripheral side of the cutting edge located on the tip side and that is located on the inner peripheral side of the tip of the tool body and inclines toward the outer peripheral side toward the tool tip side The rotation locus is arranged so as to include the rotation locus of the tip portion of the tool body.

The tip does not have to be a strict regular octagon by forming a sub-cutting edge or a corner edge between adjacent cutting edges. Further, the other one of the cutting edges is positioned so as to form an angle of −5 ° to + 5 ° with respect to a plane including the rotation axis,
The side surface that is continuous with the cutting edge located on the base end side is brought into contact with the wall portion of the tip mounting seat, and this wall portion is at least the portion on the outer peripheral side from the outer peripheral edge of the cutting edge on the base end side of the tool body. You may form so that it may open toward a base end side.

[Operation] In the face milling cutter of the present invention, since the tip is a substantially regular octagonal plate, the length of the cutting edge is shorter than the size of the tip, and one of these cutting edges is a tool. It is located on the tip outer peripheral side of the main body and inclines toward the inner peripheral side as it goes to the tip end side, and another cutting edge located adjacent to the base end side of this one cutting edge and located on the outer peripheral side of the tool. Since the blade is arranged so as to be substantially parallel to the rotation axis when viewed from the tool rotation direction side, even if cutting is performed using the entire cutting edge length with the above-mentioned one cutting edge, the load due to cutting resistance Is about the same as when using a part of the total cutting edge length of a conventional tip. Moreover,
Since the cutting edges intersect with each other at obtuse angles, chipping is unlikely to occur at the intersections.Therefore, even if the usage conditions of the machine tool, work material, etc. are the same as before, cutting using the entire length of the cutting edges Processing can be performed without any trouble. On the other hand, for the cutting process of the cutting amount such that the entire cutting edge length is used in the conventional tip, it is possible to cope by using the one cutting edge and the other one cutting edge adjacent thereto. be able to.

Thus, in the front milling cutter, by cutting using the respective total cutting edge length of each cutting edge that constitutes the main cutting edge of the chip, while eliminating the unused cutting edge portion,
Considering the degree of wear of each cutting edge, eight cutting edges can be used uniformly, which is very economical.

Furthermore, the tip includes, among the cutting edges formed on the tip, the one cutting edge, a cutting edge that is continuous with the inner peripheral side of the one cutting edge and is located on the tip side of the tool body, and the tip. So that the rotation locus around the rotation axis with the cutting edge located on the inner circumference side of the cutting edge located on the side and the cutting edge located on the tip inner circumference side of the tool body includes the rotation path of the tip portion of the tool body. Therefore, the machining surface cut by these three cutting edges does not interfere with the tip of the tool body.
Therefore, at least up to the cutting depth by the one cutting edge located on the outer peripheral side of the tip of the tool body, or up to the cutting depth by the cutting edge located on the inner peripheral side of the tip of the tool body, the tool main body in the direction of its rotation axis. Since it is possible to carry out processing such as sending it out and digging in the work material, by moving the tool body from there in the direction orthogonal to the rotation axis, it is necessary to cut the recess processing that had to rely on end mills in the past. It becomes possible to apply it to the material.

Further, the other cutting edge is connected to the cutting edge located on the base end side in a state of being positioned at an angle of −5 ° to + 5 ° with respect to the plane including the rotation axis of the tool body. If the wall portion of the tip mounting seat with which the side surface is abutted is formed so that at least the outer peripheral side edge of the cutting edge on the base end side is open toward the base end side of the tool body, It is possible to secure a large space for discharging chips during the digging process, and to smoothly discharge the chips.

In addition, the above throwaway tip is a positive tip,
By setting the axial rake angle of the one cutting edge to 0 to 25 ° and the clearance angle of 5 to 30 °, at least the sharpness of the one cutting edge can be improved and the cutting resistance can be reduced. it can. Here, if the axial rake angle exceeds 0 ° and is on the negative angle side, such sharpness cannot be improved. On the contrary, the axial rake angle
If it exceeds 25 ° or if the clearance angle exceeds 30 °, a sufficient edge angle cannot be secured and the strength of the cutting edge deteriorates, which may impair the above-described chipping prevention effect. Further, if the clearance angle is less than 5 °, flank wear is promoted, which also results in shortening the chip life.
[Embodiment] FIGS. 1 to 11 show an embodiment of a throwaway type front milling cutter of the present invention, in which reference numeral 10 denotes a tool body. The tool body 10 is attached to a main shaft of a milling machine or the like, and has a cylindrical mounting portion 12 that rotates around a rotation axis O, and a head portion 13 formed at the tip of the mounting portion 12.
It consists of and. The head portion 13 has a thick disk shape, and the outer peripheral portion of the tip is formed in the shape of an annular ridge that rises one step beyond the inner peripheral portion of the tip, and the outer peripheral portion of the tip is shown in FIG. As shown, the concave chip pocket 14
Are formed at equal intervals in the circumferential direction.

A groove-shaped chip mounting seat 15 is formed on the wall surface of each chip pocket 14 that faces the direction of rotation, and a seat member 16 is fixed to the chip mounting seat 15 as shown in FIGS. 3 and 4. It is fixed by screws 17. A chip 20 is provided on the upper surface of the sheet member 16, and is provided between the upper surface 21 and a wall surface 23 of a recess 22 formed on the bottom surface of the chip pocket 14, and is wedged into the recess 22 by a clamp screw 24. It is detachably fixed by the member 25.

The chip 20 has a substantially octagonal plate shape whose upper and lower surfaces are parallel to each other, and is a positive chip in which the upper surface 21 and the side surface, which are rake surfaces, intersect each other at an acute angle. Cutting edges 30a to 30h intersecting each other at an acute angle are formed on one ridge line portion, and a sub-cutting edge 31 is further formed at the intersection of each cutting edge 30a. The tip 20 has one cutting edge indicated by the reference numeral 30a located on the outer peripheral side of the tip of the tool body 10 and has a corner angle of about 45.
Inclining toward the inner peripheral side as it goes toward the tip side so that it becomes °, and the tool rotation of the other cutting edge 30b located on the outer peripheral side of the tool adjacent to the base end side of this one cutting edge 30a When viewed from the direction side, the cutting edge 30a is made to be substantially parallel to the rotation axis O, and the cutting edge 30a is solely used as a main cutting edge, or the cutting edge 30b and the cutting edge 30b are combined and arranged on the tool body 10 as a main cutting edge 30ab. The side surface continuous with the cutting edge 30f located on the side and the cutting edge 30d located on the base end side is brought into contact with the wall surface 15a of the chip mounting seat 15 for positioning and fixing. Further, in this state, the chip 20 is, as shown in FIG. 1 to FIG. 5 or FIG.
The one cutting edge 30a located on the outer peripheral side of the tip of the tool body 10
And the tool body 10 which is connected to the inner circumference side of the one cutting edge 10a.
Of the cutting edge 30h located on the tip side of the cutting edge 30h, further on the inner peripheral side of the cutting edge 30h, and the cutting edge 30g which is located on the inner peripheral side of the tip of the tool body 10 and inclines toward the outer peripheral side toward the tip side. The rotation locus around the rotation axis O includes the rotation locus of the tip outer peripheral portion that rises like a bank of the tool body 10, that is, the cutting edge 30a, rather than the rotation locus of the tip outer peripheral portion of the tool body 10.
The rotation loci of 30h and 30g are arranged so as to spread one step toward the tip outer peripheral side, the tip end side, and the tip inner peripheral side of the tool body 10, respectively.

When the cutting edge 30a is singly used as the main cutting edge by the front milling cutter having the above-mentioned configuration, as shown in FIG. 5, while turning the tool body 10 around the rotation axis O, the work material A is cut. cut to the two-dot chain line in FIG. L ₁ with its entire cutting edge length cutting edge 30a of the chip 20, by moving in a direction perpendicular to the rotation axis of O, excised workpiece a. Further, in the case of processing the more deep trenches, using a major cutting edge 30ab plus cutting 30b the cutting edge 30a, the tool body 10 further subsequent to incision until the two-dot chain line L ₁ cutting edge By cutting the entire cutting edge length of 30b downward to the chain double-dashed line L ₂ in the figure and moving it in the direction orthogonal to the rotation axis O, the cutting edges 30a, 30b, the auxiliary cutting edge 3
The work material A is further cut by 1. Then, by repeating the above process a predetermined number of times, the groove M having a desired depth is formed.

In the above face milling machine, the tip 20 has a substantially octagonal plate shape, and the length of the cutting edge 30a is shorter than the size of the tip 20, so that the entire length of the cutting edge 30a is used as described above. Even if the flat surface cutting is performed, the load due to the cutting resistance is about the same as when using a part of the total cutting edge length of the conventional tip. Moreover,
Since the cutting edges 30a ... intersect with each other at an acute angle,
Chips are unlikely to occur at the ends of the cutting blades 30a. Therefore, even if the conditions of the machine tool and work material are the same as before, the cutting edge
The cutting process using the entire length of 30a can be performed without any trouble. With this, it is possible to eliminate the unused cutting edge portion, and in consideration of the degree of wear of each cutting edge 30a to 30h, rotate the chip 20 as appropriate, so that the eight cutting edges 30a to 30h are evenly distributed. Very economical as it can be used.

Moreover, since the tip 20 has a substantially regular octagonal shape,
The posture and position when 20 is rotated and mounted can be made constant, and as a result, the cutting edge 30a which is the main cutting edge is formed.
The position of ... and its axial rake angle and radial rake angle can be made constant.

Further, in the throwaway type face milling machine, as shown in FIG. 7, if the mounted chip 20 is formed in an octagonal shape so as to circumscribe the inscribed circle of the conventional rectangular chip 4, the chip 4 of The same cut amount 1 as the cut amount corresponding to one side can be realized by using two adjacent sides of the chip 20. Therefore, the one cutting edge 30a and the other cutting edge 30b adjacent to the one cutting edge 30a are the main cutting edges 30
By using it as ab, it becomes possible to sufficiently cope with such a deep depth of cut. Further, in addition to this, by forming the chip 20 into a substantially regular octagonal shape, the hatched portion in the drawing becomes unnecessary, so that the material cost of the chip 20 can be reduced.

Further, in the above face milling cutter, the tip 20 is attached to the wall surface 15a.1 of the tip mounting seat 15 by the cutting resistance acting on the cutting edge 30a.
Since it is strongly tightened by 5a, the clamping strength of the tip 20 becomes higher.

In addition, in the front milling cutter, the one cutting edge 30a located on the outer peripheral side of the tip of the tool body 10, the inner cutting edge connected to the cutting edge 30h, and the cutting edge 30h located on the tip side of the tool, further connecting to the inner peripheral side. The rotation locus around the rotation axis O with the cutting edge 30g that is located on the inner circumference side of the tip of the tool body 10 and inclines toward the outer circumference toward the tip side includes the rotation locus of the outer circumference of the tip end of the tool body 10. Since the tip 30 is a positive tip as described above, by providing a positive clearance angle on the clearance surface of the cutting edge 30g, it is possible to perform a recessing process as in an end mill.

That is, as shown in FIG. 8 (a), first, the tool body 10 is rotated and fed in the direction of the rotation axis O, and the cutting blades 30a, 30g, 30h of the chip 20 are used to form a ring shape on the work material A. Dig the groove M. Next, by moving the tool body 10 in a direction orthogonal to the rotation axis O, the cutting blade 30g removes the central portion C shown by the diagonal lines in the drawing, and the surface of the work material A as shown in FIG. The oval recess B can be formed. Here, in the above face milling cutter, the rotation loci of the cutting blades 30a, 30h, 30g include the rotation locus of the tip portion of the tool body 10 as described above, and therefore, the groove M is dug or the center thereof. When the part C is removed, as shown in FIG. 8A, the machining surface of the work material A cut by these three cutting edges 30a, 30h, 30g and the tip of the tool body 10 interfere with each other. There is no. Therefore, in the face milling machine as described above, it is possible to perform the recess processing, which conventionally had to rely on the end mill, without any trouble, and it can be applied to a tool such as a machining center.

By the way, in the above face mill, the tool body 10
The problem is how to deal with the chips when the shavings are sent in the direction of the rotation axis O to dig. That is, when the tool body 10 is fed in the direction orthogonal to the rotation axis O, intermittent cutting is performed, so that the chips stored in the chip pocket 14 are discharged to the outside each time the tool body 10 makes one revolution. In the case of embedding, continuous machining is performed, and furthermore, wide cutting chips are produced by the entire cutting edges 30a, 30h, 30g. For this reason, especially when machining a deep groove as shown in FIG. 5, there is only an escape area for chips, and the wall of the chip mounting material 15 obstructs the outflow of chips to cause chip clogging. Is concerned.

Therefore, the other cutting edge 30b located on the outer peripheral side of the tool body 10 is -5 ° with respect to the plane including the rotation axis of the tool body.
In a state of being positioned so as to form an angle of + 5 °, the wall portion of the tip mounting seat 15 with which the cutting edge 30d located on the base end side abuts, at least from the outer peripheral edge P of the cutting edge 30d. If the side portion is formed so as to be opened toward the base end side of the tool body 10, chips will not be caught on the outer peripheral edge of the chip mounting seat 15, and since the chip discharge space is large. , And can be smoothly discharged toward the base end side (see FIG. 8B). In this case, the tip mounting seat
The position of the outer peripheral edge of the wall portion 15 may be aligned with the position of the outer peripheral edge P of the cutting edge 30d.

Further, by arranging the cutting edge 30b in parallel with the plane including the rotation axis O, the cutting edge 30b plays a so-called further role when feeding the tool body 10 in the direction of the rotation axis O in the digging process. Therefore, the side wall of the recess can be finished smooth.

On the other hand, the tip 20 is a positive tip in which the upper surface 21 which is the rake surface and the side surface intersect at an acute angle, and the axial rake angle of the one cutting edge 30a which is the main cutting edge is 0 to 2
If the clearance angle is set to 5 ° and the clearance angle is set to 5 to 30 °, the sharpness of the cutting edge 30a or the main cutting edge 30ab can be improved, and the cutting resistance can be reduced. In this case, when the above axial rake angle exceeds 0 ° and becomes a negative angle side, such sharpness cannot be improved, and conversely, the axial rake angle exceeds 25 ° or the clearance angle exceeds 30 °. However, if the cutting edge strength is not sufficient and the cutting edge strength deteriorates, the above-mentioned tip 20
There is a possibility that the chipping prevention effect may be impaired. Further, if the clearance angle is less than 5 °, flank wear is promoted, which also results in shortening the chip life. In this case, cutting edge 30c
Since the clearance angle is also positive, as shown in FIG. 11, the back surface of the work material A can be chamfered.

"Other Embodiments" FIGS. 12 to 15 show another embodiment of the throwaway type face milling machine according to the present invention, in which the same parts as those shown in FIGS. The same reference numerals are given and the description thereof is omitted.

The throwaway type front milling cutter shown in FIGS. 12 to 15 differs from that shown in FIGS. 1 to 4 in the mounting structure of the chip 20.

That is, the chip 20 is detachably fixed to the chip mounting seat 40 formed in the outer peripheral portion of the head 13 and having a groove shape by the mounting screw 41. This fixing state will be described in detail. As shown in FIG. 15, a through hole is formed in the center of the chip 20.
42 is formed, and at the upper part of this through hole 42 is formed a taper portion 43 that gradually increases in diameter as it goes upward.

On the other hand, a circular counterbore 44 is formed on the mounting seat 40, and a female screw portion 45 is formed at the back of the counterbore 44.

Further, in the mounting screw 41, an engaging portion 47 that engages with the tapered portion 43 is formed in the head portion 46, and a columnar portion 48 that engages with the spot facing portion 44 is provided at the lower end portion of the engaging portion 47. Further, a male screw portion 49 to be screwed into the female screw portion 45 is formed at the lower end of the columnar portion 48, and the chip mounting seat 40 has the chip 20 with the taper portion 43 of the through hole 42. Is engaged with the engaging portion 47 of the mounting screw 41, the lower end portion of the columnar portion 48 is engaged with the spot facing portion 44, and the male screw portion 49 is screwed into the female screw portion 45, thereby being detachably fixed. ing.

In the face milling machine having the above-mentioned structure, it is possible to obtain the same effects as those of the above-mentioned embodiment, but it is possible to obtain the following new effects.

That is, in the face milling machine having the above-mentioned configuration, since it is possible to perform cutting by using a plurality of adjacent cutting edges as main cutting edges, the chip 20 acts on the chip 20 at the time of cutting as compared with the conventional one in which the rectangular chip 4 is mounted. The load applied tends to increase. For this reason, the cutting resistance is due to the engaging portion of the mounting screw 41.
It is transmitted via 47 and tries to bend the male screw portion 49. However, the cylindrical portion 48 formed at the upper end of the male screw portion 49 engages with the counterbore portion 44 having the chip mounting seat 40 to prevent the male screw portion 49 from bending, and the seat of the chip 20 is seated. The stability can be further improved.

[Advantage of Device] As described above, according to the throwaway type front milling cutter of the present invention, the throwaway tip mounted on the outer peripheral portion of the tip of the tool body is a substantially regular octagonal plate-shaped positive tip, and A cutting edge is formed on each ridge portion of one surface forming a regular octagon that is a rake surface, and one of the cutting edges is directed toward the tool rotation direction side. It is located on the tip outer peripheral side of the main body and inclines toward the inner peripheral side as it goes to the tip end side, and another cutting edge located adjacent to the base end side of this one cutting edge and located on the outer peripheral side of the tool. The blade is substantially parallel to the rotation axis when viewed from the tool rotation direction side, and further the one cutting blade, and a cutting blade that is connected to the inner peripheral side of the one cutting blade and is located on the tip side of the tool body. ,
The rotation locus around the rotation axis with the cutting edge that is connected to the inner peripheral side of the cutting edge located on the tip side and is located on the inner peripheral side of the tip of the tool body and inclines toward the outer peripheral side toward the tip side. Since the cutting tool is arranged so as to include the rotational trajectory of the tip of the tool body, the length of the cutting edge is shorter than the size of the tip, and therefore, cutting is performed using the entire cutting edge length. Even if the machining is performed, the load due to the cutting resistance is almost the same as when using a part of the entire cutting edge length of the conventional tip. Moreover,
Since the cutting edges intersect each other at an acute angle, it is difficult for a chip to occur at their intersection. Therefore, even if the conditions of the machine tool, work material, etc. are the same, it is possible to perform cutting work using the entire length of the cutting edge without any problems, eliminating unused cutting edge parts and wear of each cutting edge. By appropriately rotating the chip in consideration of the degree of, the eight cutting edges can be used uniformly, so that the excellent effect of being very economical can be obtained.

On the other hand, even for the cutting process of a deep cutting depth such as using the entire cutting edge length of the conventional tip, in addition to the above one cutting edge, another one cutting edge is also used as a main cutting edge. It is possible to deal with this.

Further, since the rotational loci of the cutting blades located on the outer peripheral side of the tool body, the distal end side, and the inner peripheral side of the tip include the rotational locus of the tip part of the tool body, cutting with these cutting blades is performed. Since the tool body does not interfere with the machined surface, it is possible to perform not only flat surface cutting but also all kinds of machining such as recess machining, and it can also be applied to tools for machining centers.

Further, the other cutting edge located on the outer peripheral side of the tool body is -5 ° to +5 with respect to the plane including the rotation axis of the tool body.
At the outer edge of the cutting edge on the base end side, at least the wall of the tip mounting seat where the side surface that is continuous with the cutting edge located on the base end side makes contact with the cutting edge at the base end side. If it is formed so that the part on the outer peripheral side is opened toward the base end side of the tool body, it is possible to secure a large chip discharge space during digging, and to perform the discharge smoothly. it can.

In addition, the above throwaway tip is a positive tip,
And, by setting the axial rake angle of the one cutting edge to 0 to 25 ° and arranging the clearance angle to be 5 to 30 °, it is possible to improve the sharpness of the main cutting edge and reduce the cutting resistance. You can

[Brief description of drawings]

1 to 11 show one embodiment of the front milling cutter of the present invention, and FIG. 1 is a side view of the front milling cutter,
2 is a plan view of the same, FIG. 3 is a view taken in the direction of arrow III in FIG. 1, FIG. 4 is a view taken in the direction of arrow IV in FIG. 3, and FIG. Fig. 6 is a plan view of the machined work material, Fig. 7 is a plan view of the chip, and Fig. 8 (a) is a plan view of the work material cut using a face mill. Fig. 8 (b) is a side sectional view showing a modification of the front milling cutter, Fig. 9 is a plan view of a work material that has been cut, and Fig. 10 is Fig. 8 FIG. 11 is a side sectional view showing a state in which the work material is being cut, and FIGS. 12 to 15 show another embodiment of the present invention. Fig. 12 is a side view of the front milling cutter, Fig. 13 is the same plan view, and Fig. 14 is XI in Fig. 12.
FIG. 15 is a side sectional view showing a chip mounting structure, and FIG. 16 is a side view showing an example of a conventional face mill. 10: Tool body, 15: Tip mounting seat, 15a: Wall surface, 2
0 …… Throw away tip, 30a, 30b, 30f …… Cutting edge, 30
ab …… Main cutting edge.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-60-85817 (JP, A) JP-A-48-65578 (JP, A) JP-B-56-23723 (JP, B2)

Claims (3)

(57) [Scope of utility model registration request] 1. A throw-away type face milling machine in which a tip mounting seat is provided on the outer periphery of the tip of a tool body that rotates around a rotation axis, and a throw-away tip is detachably mounted on each tip mounting seat. A tip
In addition to forming a substantially regular octagonal plate-shaped positive tip, a cutting edge is formed on each ridge line portion of one surface forming a regular octagon that is a rake surface, and this one surface is directed to the tool rotation direction side, One of the cutting blades is positioned on the outer peripheral side of the tip of the tool main body so as to incline toward the inner peripheral side toward the tip side, and adjacent to the base end of the one cutting edge. The other cutting edge located on the outer peripheral side of the tool is connected to the one cutting edge and the inner peripheral side of the one cutting edge so that the other cutting edge is substantially parallel to the rotation axis when viewed from the tool rotation direction side. A cutting blade located on the tip side of the tool body, and a cutting edge located on the tip side of the tool body. The cutting edge is located on the inner circumference side of the tool body and is inclined toward the outer circumference side toward the tip side. The rotation locus around the rotation axis with the cutting edge that includes the rotation locus of the tip portion of the tool body is included. Indexable face milling cutter, characterized in that the sea urchin arranged. 2. A cutting blade positioned on the base end side, wherein the throw-away tip is positioned such that the other cutting blade forms an angle of −5 ° to + 5 ° with respect to a plane including the rotation axis. The side surface that is continuous with the tip mounting seat is brought into contact with the wall portion of the tip mounting seat, and the wall portion is opened at least from the outer peripheral side edge of the cutting edge on the base end side toward the base end side of the tool body. The throw-away face milling cutter according to claim 1, wherein the throw-away face milling cutter is formed as follows. 3. The throw-away tip is arranged such that the axial rake angle of the one cutting edge is 0 to 25 ° and the clearance angle is 5 to 30 °.
Throw-away type face milling machine described in.