JPH05309514A - Throw away tip - Google Patents

Abstract

PURPOSE:To set an axial rake angle and a radial rake angle as widely as possible in the conformal side, as keeping the thickness of the end part of a cutting tool main body holding a tip main body. CONSTITUTION:An end face 33, which is a cutting face of a tip main body 32, is made to be an inclined face which inclines toward the other end face 42, which is a bearing face, as separating from a nose part 34 with inclination. With this structure, the ridge lines formed by the side faces 35, 36 facing across the nose part 34 with each other and the end face 33, are cutting edges 37, 38, each of which also inclines toward the other end face 39 with inclination beta. A breaker 40 is formed along the cutting edge 37. The axial rake angle and the radial rake angle are set in the conformal side, at an angle corresponding to the sum of the inclination beta and the angle of the inner face of the breaker 40. In this way, the cutting quality can be raised as keeping the rigidity of the end part 2 of a cutting tool main body holding the tip 31.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a throw-away tip mounted on various kinds of throw-away tools.

[0002]

2. Description of the Related Art As a throw-away type tool equipped with such a throw-away tip (hereinafter referred to as a tip), for example, a throw-away type end mill whose tip portion is shown in FIGS. Are known.

In this end mill, the thickness of the tip portion 2 is gradually increased from the tip portion 2 of the tool body 1 having a multi-columnar shape whose diameter is reduced toward the tip toward the base end side in the direction of the tool axis C. The chip pocket 3 is formed so as to be large. A tip mounting seat 5 is formed on the bottom surface 4 of the tip pocket 3 on the tip side in the tool axis C direction and facing the corner on the side facing the tool rotation direction. The chip 7 is thus fixed.

The chip 7 is a flat type positive chip in which one end surface 9 of the chip body 8 which is the rake face forms a substantially parallelogram in a plan view. The one end surface 9 and the chip mounting seat 5 are provided. The other end surface 10 of the chip body 8 which is in contact with and serves as a seating surface is formed to be parallel to each other. Further, the nose portions 11, 11 of the tip 7 are formed on a pair of acute-angled portions located on one diagonal of the parallelogram forming the one end face 9, respectively. Then, the side surfaces 12 adjacent to each other with the nose portion 11 of the chip body 8 interposed therebetween,
Intersection ridgeline 1 formed by each of 13 and the one end surface 9
Cutting edges 16 and 17 are formed so as to be continuous with the nose portion 11 on four sides of the parallelogram-shaped nose portion 11 forming the one end surface 9, respectively. It is a side cutting edge and a bottom cutting edge. Further, a mounting hole 18 is formed in the central portion of the chip body 8 so as to penetrate in the thickness direction of the chip body 8.

On the other hand, in the tip mounting seat 5 on which the tip 7 is mounted, the above-mentioned cutting edges 16 and 17 project from the outer peripheral surface and the tip surface of the tip portion 2 of the tool body 1 when the tip 7 is mounted. It is formed in a shape that engages with the outer shape of the chip body 8. In addition, the other end surface 10 of the chip body 8
Similarly to the bottom surface 4 of the chip pocket 3, the bottom surface 19 of the tip mounting seat 5 on which the tool is mounted is such that the wall thickness H of the tip portion 2 of the tool body 1 gradually increases from the tip of the tool body 1 toward the base end side. In addition, the flat surface is formed by inclining in a direction oblique to the tool axis C.

Further, a screw hole (not shown) is provided in the center of the bottom surface 19 of the chip mounting seat 5, and the axis of the screw hole is the chip body 8 when the chip 7 is mounted on the chip mounting seat 5. Is slightly eccentric toward the corner of the tip mounting seat 5 on the base end side in the tool axial direction from the axis of the mounting hole 18 formed in the central portion of the. In addition, an oval recess 20 is formed in a plan view at a corner of the tip mounting seat 5 on the base end side in the tool axis direction.

In the indexable end mill having such a structure, the tip 7 is mounted on the tip mounting seat 5 of the tool body 1 and the clamp screw 6 is tightened, so that the other end surface 10 of the tip body 8 is mounted on the tip mounting seat 5. The chip 7 is seated and fixed by being pressed by the bottom surface 19 of the. Along with this, the chip body 8 is pressed against the corner side of the chip mounting seat 5 by the eccentricity between the axis of the screw hole of the chip mounting seat 5 and the axis of the mounting hole 18 of the chip body 8, whereby the chip body 8 is pressed. Tool body 1 side face 1 located on the base end side
2 and the side surface 1 that is adjacent to the side surface 12 with the nose portion 11 interposed therebetween.
3 and the wall portions 21 and 22 of the tip mounting seat 5 are brought into contact with each other, thereby projecting from the outer peripheral surface of the tip end portion 2 of the tool body 1 and the outer peripheral side cutting edge of the end mill and the bottom cutting edge. The positions of the cutting blades 16 and 17 are accurately positioned. Further, in the end mill of this example, the recesses 20 formed in the corners of the tip mounting seat 5 prevent contact of the tip 7 near the nose portion 11 with the tip mounting seat 5, so that the cutting edges 16 and 17 are provided. There is an advantage in that the positioning accuracy of can be maintained and the molding of the chip mounting seat 5 itself can be facilitated.

[0008]

By the way, in such a throw-away type tool, since a large cutting resistance acts on the tip 7 which comes into contact with the work material and cuts it, a tool holding the tip 7 is held. It is desirable that the tip portion 2 of the main body 1 be designed so as to have sufficient rigidity. Therefore, in the end mill shown in FIGS. 13 to 15, as described above, the tip pocket 3 is formed such that the wall thickness of the tip portion 2 gradually increases from the tip of the tool axis C toward the base end side. The tip mounting seat 5 is also a flat surface whose bottom surface 19 is inclined in a direction oblique to the tool axis C so that the wall thickness H of the tip portion 2 is gradually increased toward the tool axis C proximal end side. Is molded as.

However, when the chip 7 whose rake face and seating surface are parallel to each other is mounted on the chip mounting seat 5 whose bottom surface 19 is thus inclined, the rake face also corresponds to the chip mounting seat 5. It becomes an inclined surface parallel to the bottom surface 19. That is, when the angle formed by the bottom surface 19 of the tip mounting seat 5 and the tool axis C is θ as shown in FIG.
The absolute value of the axial rake angle γa ₁ of the mounted tip 7 is θ
It becomes unavoidable that the negative angle becomes equal to, and thus the machinability deteriorates.

On the other hand, the radial rake angle γr of the rake face
_When the outer diameter of the tip portion 2 of the tool body ₁ is the same, ₁ is determined by the wall thickness H of the tip portion 2 and the wall thickness of the tip body 8. However, as described above, in order to give the tip portion 2 of the tool body 1 sufficient rigidity, the wall thickness H of the tip portion 2 cannot be made too small, and considering the rigidity of the tip 7, the tip body 2 Since it is difficult to reduce the wall thickness of No. 8, the radial rake angle γr ₁
Also has to be increased to the negative side, which leads to further deterioration of the machinability.

In view of the above circumstances, the applicant has filed a Japanese Patent Application No. 3-42.
No. 052 proposed a throw-away tip. In this throw-away tip, the top surface of the throw-away tip, which has a polygonal shape in plan view, is inclined in a direction in which the thickness becomes smaller as the distance from the nose portion increases. While ensuring the rake angle in the forward direction, the thickness of the tool body is ensured. An object of the present invention is to further improve the throw-away tip to further improve the advantage that the tool body has high strength and good sharpness.

[0012]

In order to achieve the above object, the invention of claim 1 is such that a nose portion is formed at a corner of a polygonal plate-shaped tip body, and the tip sandwiches the nose portion. A throw-away tip in which a cutting edge is formed so as to be continuous with the nose portion on at least one of two intersecting ridge lines formed by each of a pair of adjacent side surfaces of the main body and one end surface of the tip body that is continuous with the nose portion. In, the one end surface has an inclined surface toward the other end surface side of the chip body as it separates from the nose portion, and the two intersecting ridge lines are also separated from the nose portion by the inclined surface. Being inclined toward the end face side, and a breaker is formed on each of the inclined surfaces along a ridgeline formed by these inclined surfaces and each of the side surfaces. And it features.

According to a second aspect of the present invention, in the throw-away tip according to the first aspect, one end face of the chip body has a quadrangular shape in plan view, and is located on one diagonal line of the quadrangle forming the one end face. The nose portion is formed on both of the pair of corner portions, and the one end surface of the chip body is another diagonal line of the one end surface due to the inclined surface which is directed toward the other end surface side of the tip body as it is separated from the nose portion. It is characterized in that it is formed in a V-shape when viewed from the side along. According to a third aspect of the present invention, in the first or second aspect, the inner surface of the breaker is a rake surface that is further inclined in the positive direction with respect to the cutting edge from the one end surface. According to a fourth aspect of the invention, in the third aspect, the ridgeline of the valley of the breaker is inclined with respect to the cutting edge in a plan view.

[0014]

According to the above construction, the one end surface serving as the rake surface of the tip has the inclined surface toward the other end surface side of the chip body, that is, the seating surface side as the tip surface is separated from the nose portion. The two intersecting ridge lines formed by each of the two side surfaces sandwiching the nose portion and the one end surface also incline toward the seating surface side as they are separated from the nose portion. Therefore, when such a tip is mounted on a throw-away tool in which the bottom surface of the tip mounting seat described above is inclined so that the wall thickness of the tip portion gradually increases as it goes toward the tool body proximal end side, By making the inclination of the intersecting ridge line, which is located on the outer peripheral side of the tool, of the intersecting ridge line larger than the inclination of the bottom face of the insert seat, the inclination of the bottom face of this insert seat is offset, resulting in the axial rake of the insert rake face. The corners can be set to conformal. In this case, of the two intersecting ridge lines, the intersecting ridge line located on the tool tip side also inclines from the nose portion to the seating surface side of the tool body, so that the rake angle in the radial direction of the rake face is also more regular than the conventional one. Can be set to the side.

Further, the tip portion of the tool main body for holding the tip can be designed so that its wall thickness gradually increases toward the base end side of the tool axis as in the conventional case, so that the rigidity of this portion is impaired. There is no such thing.
Therefore, according to the present invention, the axial rake angle and the radial rake angle of the rake surface are set to the right angle side while maintaining the rigidity of the tip end portion of the tool main body that holds the chip with one end surface serving as the rake surface of the chip. It is possible to improve the machinability.

In addition, since the breaker is formed along the cutting edge, the rake angle of the cutting edge is set in the positive direction by this breaker, which improves the cutting performance and the rigidity of the tool body. It gets even bigger. Further, since the valley line of the breaker is inclined with respect to the cutting edge, the interval between the breaker and the cutting edge is optimally set at each position of the cutting edge having different cutting conditions.

[0017]

1 to 12 show an embodiment of the present invention. As shown in these figures, the tip 31 of the present embodiment is a positive type in which one end surface 33 of the tip body 32, which is the rake face of the tip 31, forms a parallelogram in plan view as shown in FIG. Noses 34, 34 are formed on a pair of acute-angled portions located on one diagonal of the parallelogram. Also, a pair of side surfaces 35, 3 adjacent to each other with the nose portion 34, 34 interposed therebetween.
6 (in the embodiment, a flank having a clearance angle of 11 °) and the one end face 33 form intersecting ridge lines 37 and 38, that is, two sides sandwiching the parallelogram acute angle portion.
4 is a cutting edge that becomes the cutting edge 37 on the outer peripheral side and the cutting edge 38 on the bottom when the tip 31 is mounted on the throw-away tool as described above.

The one end surface 33 of the chip body 32 is
Is the other end surface 3 of the chip body 32 that becomes the seating surface of the chip 31 as it goes away from the nose parts 34, 34 toward the other diagonal side connecting the obtuse angle parts of the parallelogram.
As a result, the two intersecting ridgelines 37 and 38 are also inclined toward the other end face 39 side as they are separated from the nose portion 34, and thus the one end face 33 is formed. As shown in FIG. 3, it is formed in a V shape when viewed from the side along the other diagonal line. In this embodiment, the other end surface 39 of the tip body 32 is a flat surface perpendicular to the thickness direction of the tip body 32 as shown in FIG. 3 and is a seating surface for the tip seat of the tool body. ..

The parallelogram forming the contour of the chip 31 has the contour of the other end surface 39 in plan view as shown by the broken line in the figure along the inclination of the side surfaces 35 and 36 of the chip body 32. The shape is almost the same as the plan view shape when enlarged in the direction orthogonal to the paper surface. Then, the chip body 32
The cutting edges 37, 38 of the tip end surface 33 of the tip body 32 are
Due to the inclination of the parallelogram sides s1 and s2 indicated by the two-dot chain line in the figure, θ1 (θ1 = 1 ° in the example) and θ2 (θ2 = 2 ° 30 ′ in the example), respectively.
It will be formed at a position shifted by only. The cutting blades 37 and 38 are formed between the one end surface 37 of the tip body 32 and the side surface 35 or 36, and all of these surfaces are formed by using a grinding wheel as an end surface or a side surface of the tip 31. It is formed by performing a process of moving in a two-dimensional plane set to a predetermined angle once or by changing the feeding direction as necessary. Therefore, for example, the cutting edge 37 on the outer peripheral side, which is the line of intersection of the plane that is the one end face 33 and the plane that is the side face 35, is linear.

On one end face 33 of the chip body 33, a breaker 40 is provided along each outer peripheral cutting edge 37, 37.
Are formed. These breakers 40 have a cross-sectional shape as shown in FIG. 7, and their valley lines 41 are inclined with respect to the cutting edge 37 on the outer peripheral side as shown in FIG. Further, the breaker 40 is provided, for example, in a tool grinder with a grinding tool in a plane parallel to the other end surface 39.
It is formed by linearly moving along (along the direction inclined with respect to the cutting edge 37). Therefore,
The cut in the grinding process is gradually changed based on the inclination of the one end face 33, and the width and depth are gradually reduced from the front end side to the base end side.

The breaker 40 includes the cutting edge 3 on the outer peripheral side.
7 and the bottom cutting edge 38 are formed slightly inward, and the planar land portions 42, 43 are formed along the outer cutting edge 37 and the bottom cutting edge 38, respectively.
Is caused. Further, in the embodiment, the width of the land portion 43 of the bottom cutting edge 38 having a large cutting resistance is made larger than that of the land portion 42 of the outer peripheral side cutting edge 37 to prevent chipping of the bottom cutting edge 38 while the outer peripheral side Cutting edge 3
No. 7 is designed so that a good cutting surface can be obtained.

One inner surface 44 of the breaker 40 is scooped in a direction orthogonal to the cutting edge 37 on the outer peripheral side, and is a rake surface scooped in the forward direction with respect to the land 42. On the other hand, the other inner surface 45 is a wall surface that performs a braking action. In the case of the embodiment, the other inner surface 4
5, the depth from the nose 34 is set to 0.2 mm,
The one inner surface 44 is inclined in the negative direction by θ3 (θ3 = 12 ° in the embodiment).

Reference numeral 46 is a through hole which is provided so as to penetrate through the central portion of the chip body 32 and into which a chip mounting screw is inserted. As shown in the other FIGS. 1 and 4, the periphery of the through-hole 46 is formed in a cylindrical shape as a whole and has a larger thickness than the other portions to secure the strength of the chip body 32 in this portion. It is like this.

Further, a chamfered portion 47 is formed at the obtuse corner of the chip body 32. The chamfered portion serves as a relief for avoiding interference with the surface to be processed when the throw-away tip is used in a ball end mill to perform pulling processing toward the axial base end side.

10 to 12 show a state in which the throw-away tip 31 having the above-described structure is attached to the tip mounting seat 5 in the tip pocket 3 of the tool body 1 of the end mill.
In this end mill, a tip pocket 3 is formed in a tip portion 2 of a tool body 1 whose diameter is gradually reduced toward the tip side in the tool axis C direction, and the bottom surface 4 of the tip pocket 3 is tip side in the tool axis C direction and the tool rotation direction. Clamp screw 6 on the chip mounting seat 5 formed at the position facing the corner on the side facing the
Thus, the chip 31 is fixed.

The tip mounting seat 5 has side surfaces 35 that sandwich one nose portion 34 of the tip body 32 when the tip 31 is mounted.
In a state where 36 is brought into contact with the wall portions 21, 22 of the tip mounting seat 5, respectively, the cutting edges 37, 38 connected to the other nose portion 34 have outer peripheral surfaces and tip surfaces of the tip portion 2 of the tool body 1, respectively. It is shaped in a more protruding shape and size. In addition, the corners of the chip mounting seat 5 where the walls 21 and 22 intersect each other are oval in plan view so that the one nose portion 34 does not contact the walls 21 and 22 when the chip 31 is mounted. A recess 20 is formed.

The bottom surface 19 of the tip mounting seat 5 on which the other end surface 42 of the tip body 32 is seated has a wall thickness H of the tip portion 2 of the tool body 1 from the tip of the tool body 1 toward the base end side. It is a flat surface that gradually decreases. Therefore, in the embodiment, a rake angle larger than the rake angle of the throw-away tip 31 itself can provide the necessary cutting performance while minimizing the decrease in the rigidity of the tool body 1.

A screw hole (not shown) is provided at the center of the bottom surface 19, and the axis line of the screw hole is the chip body 32 when the chip 31 is mounted on the chip mounting seat 5.
Is slightly eccentric from the axis of the mounting hole 46 toward the corner of the chip mounting seat 5.

In the throw-away type end mill having such a structure, by mounting the tip 31 on the tip mounting seat 5 and tightening the clamp screw 6, the other end surface 42 of the tip body 32 is pressed against the bottom surface 19 of the tip mounting seat 5. And the chip 31 is seated, and the chip mounting seat 5
Due to the eccentricity between the axis line of the screw hole and the axis line of the mounting hole 41 of the chip body 32, the chip body 32 is pressed against the corner side of the chip mounting seat. Then, by this, the side surfaces 35, 36 sandwiching the one nose portion 34 of the chip body 32 are sandwiched.
Are brought into contact with the walls 21 and 22 and project from the outer peripheral surface of the tip portion 2 of the tool body 1 and the tip surface to serve as the outer peripheral side cutting edge and the bottom cutting edge 37, 38.
The position of is accurately positioned.

In this embodiment as well, the recess 20 formed at the corner of the chip mounting seat 5 prevents the vicinity of the nose portion 34 of the chip 31 from coming into contact with the chip mounting seat 5 as in the prior art. Therefore, the positioning accuracy of the cutting blades 37 and 38 can be maintained, and the chip mounting seat itself can be easily molded.

In the above end mill, as described above, the one end face 33 is inclined at the angle α with respect to the other end face 39, so that the end face 33 is inclined in the axial direction and the diameter as compared with the case where it is not inclined. A large rake angle can be secured. In addition, the rake angle can be further set in the positive direction by the inner surface 44 of the breaker 40.

Further, the breaker 40 and the cutting edge 3 on the outer peripheral side
7 and the bottom cutting edge 38 and the land portion 4 between them.
Since 2, 43 are provided, chipping of the cutting edge can be prevented while ensuring the rake angle in the positive direction. Further, in consideration of the fact that the cutting load of the bottom cutting blade 38 is higher than that of the cutting blade 37 on the outer peripheral side, the width of the land portion 43 of the bottom cutting blade 38 is set to be larger in the land portions 42 and 43. ing. Furthermore, since the land portion 43 of the lower cutting edge 38 has a relatively wide width, it guides the chips in a straight line,
On the other hand, since the land portion 43 of the cutting edge 38 on the outer peripheral side has a relatively small width, chips can be immediately guided to the breaker 40.

Further, the width of the player 40 is gradually reduced from the front end side to the base end side of the cutting edge 37 on the outer peripheral side,
The strength can be maintained at the base end side portion where the strength tends to be insufficient due to the thin thickness of the chip body 32.

Further, since the axial rake angle of the cutting edge 37 on the outer peripheral side is relatively smaller on the tip side of the tool than on the base end side of the tool, it is continuous on the base end side of the cutting edge 37. The chips that are about to occur collide with the other inner surface 45 of the breaker 40 earlier than the tip side of the cutting blade 37 and are destroyed. On the other hand, on the tip end side of the cutting blade 37, chips can be guided to a location away from the cutting portion by the inner surfaces 44 and 45 of the breaker 40. Further, since the width and depth of the breaker 40 are sufficiently large at the tip portion where chips are generated from both the cutting blades 37 and 38, the chip discharging property is secured in this portion.

In the present embodiment, the present invention is applied to the cutting blades 37, 3
8 and the nose portion 34 are provided with clearance angles, the description has been made for the case of using a so-called positive type chip, but it is also possible to apply to a so-called negative type chip.

By the way, the inclination angle of the one end face in the present invention, that is, the one end face 33 and the other end face 3 in the above embodiment.
The angle α formed by 9 and the inclination angles β, δ formed by the cutting edges 37, 38 and the other end surface 39 by inclining the one end surface 33 are the size and shape of the tip 31, cutting conditions, etc. It goes without saying that it should be appropriately set according to However, for example, in the case of a parallelogram-shaped chip in a plan view as in the above-mentioned embodiment, which is generally frequently used, in which the angle of the acute angle portion of the parallelogram is about 85 ° to 70 °, The inclination angle α of the one end face 33 is preferably about 3 ° to 20 °, and the cutting edge 3 is inclined together with the inclination angle α.
The inclination angles β and δ formed by 7, 38 are 3 ° to 15 °, respectively.
It is preferable that the angle is 3 ° to 20 °. By the way, in the above embodiment, the narrow angle of the parallelogram is about 85 °, and the inclination angle α of the one end face 33 is about 13 °.
As a result, the inclination angles β and δ of the intersecting ridgelines 37 and 38 are approximately 5 ° and 12 °, respectively.

Here, when these inclination angles α, β, δ are smaller than the above range, that is, the one end face 33 is formed.
If the inclination is too gentle, the axial rake angle and the radial rake angle will not be arranged on the square side when the insert is mounted on a throw-away tool such as an end mill, and the above effect will not be sufficiently exhibited. There is a risk. On the contrary,
If these inclination angles α, β, and δ become larger than the above range, that is, if the inclination of the one end face 33 is too steep, the thickness of the central portion of the chip body 32 becomes too small, and the rigidity and strength of the chip itself are reduced. There is a risk of adverse effects.

Further, as described above, the present embodiment is an example in which the present invention is applied to a parallelogram-shaped chip in a plan view, but the present invention is not limited to this and, for example, in a plan view. The present invention can also be applied to other squares such as squares and diamonds, triangular chips, and pentagonal or higher polygonal chips. The appropriate ranges of the inclination angles α, β, δ are examples when the present invention is applied to a parallelogram-shaped chip in plan view, and when the chip shapes are different, these ranges are also included. There may be differences. further,
It goes without saying that these ranges may change due to differences in various cutting conditions during cutting.

It is needless to say that the breaker may have another cross-sectional shape without departing from the scope of the present invention. Further, although the case where the present invention is used for a rolling tool such as a throw-away type end mill has been described in the above-mentioned one embodiment, it is needless to say that the present invention can be applied to a bite and a boring bar.

[0040]

As described above, according to the present invention, the one end surface which is the rake surface of the tip has the inclined surface which becomes the seating surface toward the other end surface side as it is separated from the nose portion. The intersecting ridge line formed by the side surface of the chip body sandwiching the nose portion and the one end surface and forming the cutting edge is also inclined toward the other end surface side. Therefore, when such a tip is mounted on the tip mounting seat of a tool, the axial rake angle and the radial rake angle should be set to the right angle side while ensuring the wall thickness of the portion of the tool that holds the tip. It can be set to a large value, whereby it is possible to improve the machinability while maintaining the rigidity of the tool portion that holds the chip body that comes into contact with the work material and receives cutting resistance. Further, since the breaker is formed along the cutting edge on the one end face, the rake angle of the cutting edge is set to a further positive side, and the necessary rake angle can be easily secured. Therefore, it is possible to secure the thickness of the seating surface of the tool body and increase its rigidity. Furthermore, this breaker can ensure good chip discharge performance.

[Brief description of drawings]

FIG. 1 is a plan view showing an embodiment of the present invention.

FIG. 2 is a view taken along the line II-II (breaker valley line) in FIG.

FIG. 3 is a side view seen from the s2 line direction in FIG.

4 is along the line IV-IV of the chip of FIG. 1 (along the direction orthogonal to the diagonal connecting the obtuse corners of the parallelogram of FIG. 1)
It is an arrow view.

5 is a side view seen from a direction of a diagonal line connecting the parallelogram obtuse corners of FIG. 1. FIG.

6 is a side view of the chamfered portion formed in the obtuse-angled corner portion of FIG. 1 as viewed from the direction of the flank surface.

FIG. 7 is a view taken along the line VII-VII in FIG.

8 is a side view seen from the direction along the flank of the cutting edge 37 on the outer peripheral side of FIG. 1. FIG.

9 is a side view of the bottom cutting edge of FIG. 1 as seen from a direction orthogonal to a cutting edge line.

FIG. 10 is a plan view showing a state in which the tip of FIG. 1 is attached to a tool body.

FIG. 11 is a side view showing a state in which the tip of FIG. 1 is attached to a tool body.

FIG. 12 is a front view of the tool of FIG. 1 attached to a tool body.

FIG. 13 is a plan view showing a case where the conventional tip 7 is attached to a throw-away type end mill.

14 is a side view of the example of FIG. 13 as viewed from the direction A. FIG.

FIG. 15 is a front view of the example of FIG. 13 as viewed in the B direction.

[Explanation of symbols]

1 Tool body 2 Tip part 5 Tip mounting seat 31, Tip 8,32 Tip body 9,33 One end surface (rake surface) 10,39 Other end surface (seating surface) 11,34 Nose portion 12, 13, 35, 36, side surface 16, 17, 37, 38 Cutting edge C Tool axis H Thickness from the tip mounting seat bottom surface to the outer periphery of the tip of the tool body α Inclination angle of one end face 33 β Inclination angle of the cutting edge 37 on the outer peripheral side δ Cutting edge 38 at the bottom Tilt angle

Claims (4)

[Claims] 1. A nose portion is formed at a corner of a polygonal plate-shaped tip body, and each of a pair of adjacent side surfaces of the tip body sandwiching the nose portion is connected to the nose portion. At least one of the two intersecting ridges formed by the one end surface of the main body, in a throw-away tip in which a cutting edge is formed in succession with the nose portion, the one end surface of the tip body of the tip body away from the nose portion. It has an inclined surface toward the other end surface side, and by this inclined surface, the two intersecting ridge lines are also inclined toward the other end surface side as they are separated from the nose portion, and each of the inclined surfaces has A throw-away tip, wherein a breaker is formed along a ridgeline formed by the inclined surface of each of the side surfaces and each of the side surfaces. 2. One end surface of the chip body has a quadrangular shape in a plan view, and the nose portion is formed on both of a pair of corner portions located on one diagonal line of the quadrangle forming the one end surface. The one end face of the chip body is formed in a V shape in a side view along another diagonal line of the one end face by the inclined surface which is directed toward the other end face side of the tip body as it is separated from the nose portion. The throw-away tip according to claim 1, characterized in that 3. The throw-away tip according to claim 1, wherein an inner surface of the breaker is a rake surface which is further inclined with respect to the cutting edge in the positive direction from the one end surface. 4. The throw-away tip according to claim 3, wherein the ridgeline of the valley of the breaker is inclined with respect to the cutting edge in a plan view.