JP3236913B2 - Indexable tip - Google Patents

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 a cutting tool holder.

[0002]

2. Description of the Related Art Conventionally, as a throw-away chip having a breaker groove, there is, for example, one shown in FIGS. The throw-away tip 1 has a substantially parallelogram plate shape, and FIG. 8 shows a plan view of the nose portion 2 having an acute angle. In the figure, an upper surface 3 opposing a lower surface forming a seating surface.
A projecting surface 4 for tip clamping is formed at the center of the projection, and a substantially elliptical arc-shaped peninsula 4a projecting from the nose portion 2 is formed on the projecting surface 4, and the top surface 4b of the projecting surface 4 is flat. Have been. The ridge portion of the upper surface 3 is a cutting blade 6, and the cutting blade 6
Cutting blade 6a provided on nose portion 2 at sharp corner
And a cutting blade 6b provided at a side portion. Each cutting blade 6a, 6b has a land 9 over its entire circumference.
Are formed.

[0003] Between the cutting edge 6 and the protruding surface 4 is a valley line 1 at the center.
A breaker groove 10 consisting of a concave portion through which the cutting edge 6 passes is formed.
And an upright inclined surface 13. And
In the nose part 2, the breaker groove 10 is formed with a dot part 14 separated from the peninsula part 4a and the cutting blade 6a,
The top surface 14a of the dot portion 14 is a flat surface higher than the cutting blade 6. The inclined surface 14b reaching the top surface 14a is a convex curved surface. When such a throw-away tip 1 is attached to, for example, a cutting tool (not shown) with the nose portion 2 facing the distal end side, and cutting of the work material is performed, the chips generated by the cutting blades 6a and 6b are formed by dot portions. 14 and Peninsula 4
a, and is curled, flows along the breaker groove 10, and is discharged. Another example of a throw-away chip is shown in FIGS. The throw-away tip 16 is provided on the top surface 1 of the dot portion 17.
8A is different from the above-described indexable tip 1 in FIG. 8 in that the tip 7a has a teardrop shape.

[0004]

By the way, when the work material is cut with the above-mentioned indexable inserts 1 and 16, if the cutting width of the cutting blade 6 with respect to the work material becomes large, the tip side of the chip k becomes a dot. Top surfaces 14a, 17a of parts 14, 17
In the vicinity, the base end portion of the chip k collides with the peninsula 4 a of the protruding surface 4 along the upright surface 13. At this time, if the cut is shallow and the width of the chip k is narrow, the chip k is
When the chip k is deep and the width of the chip k is wide, the tip side portion of the chip k flows largely in the direction orthogonal to the cutting blade 6b and gets over the dot portions 14 and 17. For this reason, there is a disadvantage that the action of the breaker groove 10 such as curling and breaking is not sufficiently performed, and the chip processing is not sufficiently performed.

The present invention has been made in view of the above problems, and provides a throw-away insert in which chip breaking action such as chip curling and breaking can be favorably performed by a breaker groove even if the cutting width is large. Aim.

[0006]

In the indexable insert according to the present invention, the ridge of the upper surface facing the seating surface is a cutting edge, a breaker groove is formed inside the cutting edge, and the inside of the breaker groove is formed. A square in plan view that projects in the direction of the nose
In the throw-away chip in which the projection part of the shape is formed and the dot part separated from the projection part in the direction of the nose part on the breaker groove, the top surface of the dot part, the side of the throw-away chip The side facing the cutting edge of the region is linear, and the angle between the bisector of the nose and the side in plan view is equal to the angle of the bisector of the nose and the cutting edge of the side. angle is set to the following size, or
The ridge line facing the dot on the top surface of the protrusion is a straight line.
It is characterized by that. Chips generated by cutting with the cutting blade extend across the breaker groove, collide with the dots and protrusions, are curled, and are cut off, but especially on the straight side of the dots. Curls on the sides,
The breaking action is made well. At this time, if the angle formed by the bisector of the nose portion is larger than the angle formed by the bisector and the cutting edge in the side area, the chips will be short in the traveling distance when the incision width is large. Due to the collision, chip clogging is liable to occur, resulting in chipping of the cutting edge or damage to the machined surface. Conversely, if the angle is less than 0 °, which is parallel to the bisector, the chips will cross the dot portion, making it difficult for the chips to be cut or the like, and the breaker groove will not be able to perform its function sufficiently. . Preferably, the dot portion has a trapezoidal shape in plan view. Also, the top surface of the protrusion
Since the ridge line facing the dot is a straight line,
Area of the side of the straight line on the nose part side of the surface is the area of the edge on the cutting edge side
Since it is provided at a position close to the cutting edge of
Chips are bent into a U-shape into the gap between the socket and the projection
And it is easy to be broken.

[0007] The top surface of the dot portion may be a flat surface at the same height as the top surface of the protruding portion. At this time, the throw-away tip may have the same upper and lower surfaces.
When each of the top surfaces of the dot portion and the protruding portion is used as a seating surface, the seating surface is located outside the chip, so that stability of seating can be ensured. Further, the dot portion may be formed in a two-stage shape including a first dot portion rising from the breaker groove and a second dot portion reaching the top surface at a different inclination angle from the first dot portion. With the two-stage configuration, the breakability of chips, especially at low cutting depth, is improved.

The angle formed between the bisector of the nose and the side of the top surface of the dot may be set in the range of 0 ° to 30 °.

[0009]

FIG. 1 is a block diagram showing an embodiment of the present invention.
5 to FIG. 5, the same reference numerals are used for the same parts or members as those in the above-described related art, and the description is omitted. FIG. 1 is a plan view of a throw-away tip according to an embodiment, FIG. 2 is an enlarged plan view of a nose portion of FIG. 1, and FIG.
FIG. 4 is a sectional view taken along line DD of FIG.
Is a sectional view taken along the line EE in FIG. In FIG. 1, the throw-away tip 20 has a substantially polygonal plate shape, for example, a substantially rhombic plate shape, and has a substantially V-shaped vertical cross section inside a land 9 formed along the cutting edge 6 forming a ridge of the upper surface 3. A concave breaker groove 21 is formed over the entire circumference, and the breaker groove 21 is formed by a rake face 22 having a downward slope and an upright face 23 having an upward slope.

Moreover, the breaker groove 21 is formed such that the width thereof is wide at the nose portion 2 forming an acute corner portion, but gradually narrows toward the adjacent obtuse angle corner portion 24. A hole 32 for screw insertion is formed in the center of the upper surface, and a concave surface 33 having a height lower than that of the cutting blade 6, for example, is formed around the hole 32. On the outer side of the concave surface 33, a seating portion 25 is formed in the direction of the obtuse corner portion 24, and in the direction of the nose portion 2 of the acute angle corner portion, a projection portion 26 having a substantially square shape in plan view is formed. The top surface 26 a of the projection 26 is connected to the upright surface 23 of the breaker groove 21. Further, in the nose portion 2, a dot portion 28 is formed in the breaker groove 21 between the cutting edge 6a and the protruding portion 26 so as to be separated from the cutting edge 6a and the projecting portion 26, and the dot portion 28 has a substantially circular convex curved surface in plan view. First dot section 29 and first dot section 29
It is formed in two steps with the second dot portion 30 having a larger inclination angle, and the top surface 30 a of the second dot portion 30 is a plane having the same height as the top surface 26 a of the protruding portion 26. Moreover, the top surfaces 30a, 26a of the second dot portion 30 and the protruding portion 26 are provided at a position higher than the cutting blade 6.

The second dot portion 30 has a substantially trapezoidal truncated pyramid shape in a plan view, and a side 30b of the top surface 30a having a substantially trapezoidal shape and facing the cutting edge 6b has a straight line shape.
Moreover, the bisector L and the cutting edge 6 of the nose portion 2 having an acute angle in plan view
b, the angle α between the bisector L and the side 30b of the top surface 30a of the second dot portion 30 is
0 ≦ α ≦ θ (see FIG. 2). In FIG. 2, α =
It is set to about θ / 2. If the angle α is larger than θ, chip clogging may occur when the cutting width is large. Conversely, if the angle α is smaller than 0 °, the second dot 30
Will no longer function as a breaker. The angle θ is 1
The angle is set in the range of 7.5 ° to 72.5 °, and if it is smaller than this range, the strength of the nose portion is small, and if it is larger, there is a problem in cutting. Is preferably smaller than angle θ and in the range of 0 ° to 30 °. This is because chips can be optimally curled and broken with respect to the angle θ of the nose portion by the angle α in this range.

In the projection 26, a dot 28
The ridgeline 26b on the nose side of the top surface 26a facing the front surface 26a has a linear shape, and is preferably orthogonal to the bisector L. Accordingly, since the edge 26b-a of the ridgeline 26b of the projection top surface 26a is provided at a position closer to the cutting blade 6b, the breaker function of curling and breaking the chip k is enhanced. Moreover, a gap C is formed between the dot portion 28 and the protruding portion 26, and in particular, the second dot portion 30
Of the top side 30a of the top surface 30a and the cutting edge 6b of the ridge line 26b of the top surface 26a
Due to -a, the chip k is bent into a substantially U-shape, and the cutting becomes easy. In the breaker groove 21, the cutting blade 6
A substantially half-moon-shaped flat portion 31 parallel to the lower surface may be formed between the rake face 22 and the upright face 23 at a position facing b. Although the above-described configuration is for the upper surface 3 of the throw-away chip 20, the same configuration may be formed on the lower surface. In this case, not only when the chip 20 is corner-changed, but also when the chip 20 is turned over. You can also use both sides.

Since the indexable insert 20 according to the present embodiment is configured as described above, the nose portion 2 is positioned at the distal end side and attached to a cutting tool holder or the like (not shown), and the cutting blade 6a and the cutting blade 6b are provided. Is used to cut the work material. In this case, chips generated by cutting with the cutting edge 6a of the nose portion 2 and the cutting edge 6b following the cutting edge 6a are generated by the breaker groove 21.
Of the dot portion 28 and the projecting portion 26
Collide with At this time, since the side portion 30b of the top surface 30a of the dot portion 28 is linear and the angle α with the bisector L is less than or equal to θ, the chip k is brought into surface contact and is well curled, Cut and processed. In particular, even if the chip k is wide, the cutting force at the time of collision is small because the dot portion 28 and the projecting portion 26 are separated by the gap C, and the end of the top side 30b of the dot portion 28 at the projecting portion side. Of the cutting edge 6b of the ridge 26b of the nose portion of the projection 30
The chip k is bent into a U-shape and enters the gap C with the ba, and is broken. In this way, chip processing is effectively performed in the breaker groove 21.

As described above, according to the present embodiment, the chips k can be effectively curled and cut, and even if the chips k are wide, sufficient chip processing can be performed by sufficient curling and cutting. Moreover, the top surface 3 of each of the dot portion 28 and the protruding portion 26
When the throw-away tip 20 is turned upside down and used, the seating surface can be secured on the outer side of the tip because the flat surfaces 0a and 26a are the same height.
Can be fixed stably.

Next, a second embodiment of the present invention will be described with reference to FIG. 6 using the same reference numerals for the same parts as in the first embodiment. FIG. 6 is a plan view of the nose portion of the throw-away tip 39. In the drawing, the dot portion 40 has a convex-curved first dot portion 41 and a second dot portion 42 having a steeper inclination angle than the first dot portion 41. The top surface 42a of the second dot portion 42 has a substantially bullet shape in a plan view, and
2 b is formed substantially parallel to the bisector L of the nose portion 2. Therefore, the angle α is set to 0 °. According to the present embodiment, even when the cutting width is small and cutting is performed only with the cutting edge 6a, the chips are formed in the two-stage dot portion 40.
In this way, even wide chips can be reliably cut by the gap C, and efficient chip processing can be performed.

Next, a third embodiment of the present invention will be described with reference to FIG. 7 using the same reference numerals for the same parts as in the first embodiment. FIG. 7 is a plan view of the nose portion of the throw-away tip 49. In the drawing, the dot portion 50 includes a first dot portion 51 having a convex curved surface and a second dot portion 52 having a larger inclination angle than the first dot portion 51. The first dot portion 51 and the second dot portion 52 are formed so as to be sequentially connected and arranged in the longitudinal direction of the bisector L. The top surface 52a of the second dot portion 52 has a substantially triangular shape in a plan view, and both side edges 52b are formed substantially parallel to the cutting edge 6b. Therefore, the angle α = θ ゜. According to the present embodiment, chip breaking processing can be performed without causing chip clogging regardless of the width of the chip k.

In each of the above-described embodiments, the concave surface 33 is formed to be lower in height than the protruding surface 26 and the seating portion 25.
It may be the same height as the protruding surface 26 and the seating portion 25. Further, the concave surface 33 may be a flat clamp surface instead of the screw insertion hole 32 at the center. In addition, although the throw-away tips 20, 39, and 49 have a substantially rhombic plate shape, the present invention is not limited to this, and may be employed for throw-away tips of various shapes.
In addition, the throw-away tips 20, 39, 49 of the present invention.
The tool for mounting the can be mounted not only on the cutting tool or the face mill but also on various tools.

[0018]

As described above, in the throw-away tip according to the present invention, the side facing the cutting edge in the area of the side of the throw-away tip on the top surface of the dot portion is linear,
Since the angle formed by the bisector of the nose and the side in plan view is set to be equal to or smaller than the angle formed by the bisector of the nose and the cutting edge in the side area, the chips are Even if it is wide, it has the effect of colliding with the linear side of the dot portion by surface contact, being surely curled, broken, and smoothly discharged without causing chip clogging.
At this time, if the angle of the above-mentioned side is larger than the angle formed by the bisector and the cutting edge in the side area, the chip collides with the dot portion or the like in a short traveling distance when the cutting width is large, so that the chip is clogged. When the angle is smaller than the angle (0 °) parallel to the bisector, the chips can get over the dots, causing chip breakage. This has the disadvantage of being difficult to perform.

Further, since the top surface of the dot portion is a flat surface having the same height as the top surface of the protruding portion, each of the top surfaces of the dot portion and the protruding portion is used when the surface is used as a seating surface. Since the seating surface is formed outside the chip, the stability of the seating can be ensured. Further, since the dot portion is formed in a two-stage shape including the first dot portion rising from the breaker groove and the second dot portion reaching the top surface at an inclination angle different from that of the first dot portion, especially at the time of low cutting depth The processing ability of breaking chips is improved.
In addition, since the ridge line facing the dot portion on the top surface of the projection is a straight line, the chips are bent into a substantially U-shape into the gap between the dot portion and the projection, and are easily broken.

[Brief description of the drawings]

FIG. 1 is a plan view showing a throw-away tip according to an embodiment of the present invention.

FIG. 2 is a plan view of a nose portion of the throw-away tip shown in FIG.

FIG. 3 is a sectional view taken along line CC of the throw-away tip shown in FIG. 1;

FIG. 4 is a sectional view taken along line DD of the throw-away tip shown in FIG.

FIG. 5 is a sectional view taken along line EE of the throw-away tip shown in FIG. 1;

FIG. 6 is a plan view of a nose portion of a throw-away tip according to a second embodiment.

FIG. 7 is a plan view of a nose portion of a throw-away tip according to a third embodiment.

FIG. 8 is a plan view of a nose portion of a conventional throw-away tip.

FIG. 9 is a sectional view taken along line AA of the throw-away tip shown in FIG.

FIG. 10 is a plan view of a nose portion of another conventional throw-away tip.

FIG. 11 is a cross-sectional view of the throw-away tip shown in FIG.
It is a B sectional view.

[Explanation of symbols]

 2 Nose portion 6, 6a, 6b Cutting edge 20, 39, 49 Throw-away tip 21 Breaker groove 26 Projection portion 26a, 30a, 42a, 52a Top surface 28, 40, 50 dot portion 29, 41, 51 First dot portion 30 , 42,52 Second dot part

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yuichi Suzuki 1511 Furamaki, Ishishita-cho, Yuki-gun, Ibaraki Prefecture Mitsubishi Materials Corporation Tsukuba Works (56) References JP-A-6-190612 (JP, A) (58) ) Field surveyed (Int. Cl. ⁷ , DB name) B23B 27/22 B23C 5/20 B23B 27/14

Claims (4)

(57) [Claims] 1. A ridge line portion on an upper surface facing a seating surface is a cutting edge, a breaker groove is formed inside the cutting edge, and a substantially square planar view protruding inside the breaker groove toward a nose portion.
A throw-away chip in which a projected portion having a shape is formed and a dot portion separated from the projecting portion is formed in a direction of a nose portion on the breaker groove, wherein the throw-away chip has a top surface of the dot portion. The side of the region of the side of the tip facing the cutting edge is linear, and the angle formed between the bisector of the nose and the side in plan view is the bisector of the nose. ridge and the set to an angle less than the size of the cutting edge side of the area, and, opposite to the dot portion of the top surface of the projecting portion
Is a throw-away tip characterized by being a straight line. 2. The throw-away chip according to claim 1, wherein the top surface of the dot portion is a flat surface having the same height as the top surface of the projecting portion. 3. The dot portion has a two-stage shape including a first dot portion rising from a breaker groove and a second dot portion reaching the top surface at an inclination angle different from that of the first dot portion. The throw-away tip according to claim 1 or 2, wherein: The angle between the sides of wherein the top surface of the bisector of the nose portion and the dot part is 1 to claim, characterized in that it is set to 0 ° to 30 ° range 3. The throw-away tip according to any one of 3 .