JP2949973B2 - 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 insert (hereinafter abbreviated as a tip) used as a blade of a throw-away type cutting tool such as a throw-away milling machine, an end mill, or a throw-away cutting tool. In particular, the present invention relates to a chip using an ultra-high hardness sintered body such as diamond or cubic boron nitride (hereinafter abbreviated as CBN) for a cutting edge portion.

[0002]

2. Description of the Related Art As described above, when the cutting edge portion of a chip is formed from a super-hard sintered body such as diamond or CBN, such a super-hard sintered body and a super-structure constituting a chip main body are used. Because it is difficult to directly fix hard alloys and steel materials by brazing, first, this super-hardened sintered body and a hardened sintered body such as a cemented carbide are integrally formed into a layer to form a cutting blade member. This is fixed to the chip body.
As such a chip, for example, Japanese Patent Application No. 1-1082
No. 39 and Japanese Utility Model Application No. 1-108958 are known.

FIGS. 8 to 10 show an example of such a chip. The chip body 1 is made of cemented carbide or high-speed steel, and in this example, is formed into a triangular flat plate. Of the two end faces 2 and 3 of the chip body 1 facing the chip thickness direction, a corner C1 sandwiched by two mutually intersecting ridges 4 and 5 of one end face 2 has these ridges 4 and 5 therebetween. Are formed with two peripheral surfaces 6 and 7 of the chip body 1 and a notched concave portion 8 opened on the one end surface 2 respectively.

[0004] The notched recess 8 is formed with a high-hardness sintered body 9 such as a cemented carbide and a super-hardened sintered body 10 such as diamond or cubic boron nitride (hereinafter abbreviated as CBN). The cutting edge member 11 integrally formed on the chip body 1 is fixed by brazing or the like with the portion of the super-hard sintered body 10 facing one of the peripheral surfaces 6 and 7 of the chip body 1. Have been. Here, the outer surface of the cutting blade member 11 is formed so as to be smoothly connected to the one end surface 2 and the two peripheral surfaces 6 and 7 of the chip main body 1. A cutting edge 12 is formed in the portion so as to face the corner C1 and to continue to the other ridge 5 of the two ridges 4 and 5 intersecting at the corner C1.

[0005] Such a chip is mounted on a cutting tool body such as a throw-away type milling machine, end mill, or throw-away type cutting tool and used for cutting work. Here, in the chip having the above-described structure, the cutting edge 12 formed on the cutting edge member 11 is made of the ultra-high hardness sintered body 10 such as diamond or CBN having extremely high hardness, and therefore has excellent wear resistance and cutting performance. Performance can be demonstrated. On the other hand, since the portion of the cutting blade member 11 closer to the tip body 1 than the cutting blade 12 is made of a high-hardness sintered body 9 such as a cemented carbide, a relatively expensive ultra-high-hardness Union 1
The portion occupied by zero can be made as small as possible. As a result, it is possible to provide a chip which is inexpensive and can be used up by one cutting, and it becomes unnecessary to perform complicated chip management work.

[0006]

By the way, when the portion occupied by the ultra-high-hardness sintered body 10 in the cutting edge member 11 is reduced, the ultra-high-hardness sintered body 10 The bonding area on the bonding surface with the high hardness sintered body 9 also becomes small. However, as described above, the brazing strength between the super-hard sintered body 9 and the cemented carbide or high-speed steel constituting the chip body 1 is not very high, and the ultra-high hardness at which the cutting edge 12 is formed is not high. The portion of the hard sintered body 10 is in a state of being held by the chip body 1 exclusively by bonding with the high hardness sintered body 9. Therefore, when the joining area with the high-hardness sintered body 9 is also reduced in order to reduce the portion occupied by the ultra-high-hardness sintered body 10 in the cutting blade member 11, the cutting edge member 11 The bonding strength between the high-hardness sintered body 9 and the ultra-high-hardness sintered body 10 that constitutes the above also becomes small, and the ultra-high-hardness sintered body 10 is separated from the high-hardness sintered body 9 by a load acting during cutting. There was a problem that would.

[0007]

Means for Solving the Problems Here, the inventors of the present invention have conducted various tests, and as a result, have found that the cutting surface of the cutting edge member is cut at the joint surface between the ultra-hard sintered body and the high-hardness sintered body. Sometimes the direction of the load acting from the cutting edge, that is, the width of the joining surface in the direction along the chip thickness direction is equal to or more than a certain value, thereby avoiding peeling of the ultra-hard sintered body from the cutting edge member. Was found to be possible. Then, when the test was further repeated, a result was obtained in which the above-mentioned constant value was 1.0 mm.

The present invention has been made based on such knowledge to solve the above-mentioned problems, and it is an object of the present invention to provide a chip body formed into a polygonal flat plate and having a ridge edge angle of an end face in a chip thickness direction. A notch recess is formed in the portion, and in this notch recess,
A cutting blade member formed by integrally forming a high-hardness sintered body such as a cemented carbide and an ultra-high-hardness sintered body such as diamond or cubic boron nitride in a layered form, A chip fixed to the peripheral surface of the chip body and further having a cutting edge formed on the ultra-high hardness sintered body portion of the cutting blade member so as to face a corner of the edge of the chip body; The joining surface between the ultra-high-hardness sintered body and the high-hardness sintered body of the member is formed so that the flank surface of the chip connected to the cutting blade is parallel to the chip thickness direction of the bonding surface. the width in the direction not less than 1.0mm along, towards further chip thickness direction
The bottom of the notch recess with the two ridges sandwiching the corner.
From one side of the flank connected to the flank to the other side
Increasing surface gradually moving toward the above-mentioned end surface side
It is characterized in that the the.

[0009]

According to the chip having such a configuration, based on the above findings, the width of the joining surface between the ultra-hard sintered body and the high-hardness sintered body of the cutting blade member in the direction along the chip thickness direction. Is 1.0mm
As described above, the ultra-high-hardness sintered body having the cutting edge is stably and firmly joined to the high-hardness sintered body, and peeling of the ultra-high-hardness sintered body from the high-hardness sintered body is performed. Can be prevented.

[0010] In the chip having the above structure, the joining surface of the ultra-hard sintered body and the high-hardness sintered body is formed parallel to the flank connected to the cutting edge, so that the joining surface is positioned with respect to the cutting edge. Are also arranged in parallel. Thereby, even when a force acting on the cutting surface exerts a shearing force on the cutting surface due to a load acting on the cutting blade during the cutting, the shearing force uniformly acts on the bonding surface. Therefore, the load can be prevented from acting intensively on a part of the joining surface, and the occurrence of a situation in which the cutting blade member is broken by the shearing force due to such a load can be suppressed. It becomes possible. Sa
In addition, the bottom of the notch
The recess is easily formed by polishing the corner of the chip body
Cut off some of the load acting on the cutting edge.
Shear force that can parry along the bottom of the recess and acts on the joint surface
Can be made smaller.

[0011]

1 to 4 show an embodiment of the present invention. In these figures, the tip body 21 is a flat plate shaped from a cemented carbide or high-speed steel,
The two end faces 22 and 23 facing the chip thickness direction are formed in a substantially square shape. In addition, these end faces 22, 23
Of the two end surfaces 22 and 23 from one end surface 22 which becomes a rake surface at the time of chip mounting toward the other end surface 23 which becomes a seating surface. It is a so-called positive type chip.

Then, one corner C1 of the one end face 22 is formed.
Are formed with peripheral surfaces 24 and 25 respectively connected to the two ridges 28 and 29 of the one end surface 22 sandwiching the corner C1 and a cutout recess 26 so as to open to the one end surface 22. I have. The notch 26 is defined by a bottom surface 26A facing the chip thickness direction and a wall surface 26B rising from the bottom surface 26A and continuing to the one end surface 22. The bottom surface 26A has a square shape in a plan view from the one end surface 22 side, and has two ridges 2 sandwiching the corner C1.
8, 29, one peripheral surface 2 continuing to one edge 28
4 along the other ridge 29 along the other ridge 29
Is inclined toward the one end surface 22 as it goes toward the center of the vehicle.

Further, a cutting blade member 32 formed by integrally forming a high-hardness sintered body 30 such as a cemented carbide and an ultra-high-hardness sintered body 31 such as diamond or CBN into a layer is formed in the cutout recess 26.
However, the portion of the super-hard sintered body 31 is
It is fixed by brazing toward the four sides. Thereby, the cutting edge member 32 is arranged such that the joining surface 33 between the portion of the high hardness sintered body 30 and the portion of the ultra-high hardness sintered body 31 is along the thickness direction of the chip. Become.

Here, the outer shape of the cutting blade member 32 is formed so as to be flush with the one end surface 22 and the peripheral surfaces 24 and 25 of the chip body 21 so as to be flush with each other. Then, a surface 32A that is continuous with the one end surface 22 of the cutting blade member 32 and a surface 3 that is continuous with the one peripheral surface 24
A cutting edge 34 is formed at the intersection ridge line formed by 2B so as to be continuous with the one ridge 28. Accordingly, the surface 32 that is flush with the one end surface 22 of the cutting blade member 32
A is a part of the rake face of the chip, and the surface 32B that is flush with the one peripheral surface 24 is a part of the flank of the chip. Since the cutting edge member 32 has the portion of the super-hard sinter 31 made of diamond, CBN, or the like fixed to the one peripheral surface 24 side as described above, the cutting edge 34 also has this ultra high hardness. It is formed in the portion of the hardness sintered body 31.

In the present embodiment, the cutting edge member 32 has a joining surface 33 between the high-hardness sintered body 30 and the ultra-high-hardness sintered body 31 in a surface 32B continuous with the one peripheral surface 24.
Are formed and fixed so as to be parallel to the chip, that is, parallel to the flank of the chip. Further FIG.
As shown in the figure, the width d of the joining surface 33 in the direction along the chip thickness direction is set to 1.0 mm in this embodiment.

In the present embodiment, a chamfered portion 35 is formed at the intersection of the two peripheral surfaces 24 and 25 of the chip body 21, and the chamfered portion 35 is
The cutting blade 34 is extended to the cutting blade member 32 fixed to the cutting edge 34 and reaches one end of the cutting blade 34 on the corner C1 side.
In this embodiment, the joining surface 33 of the cutting blade member 32 is
The width W in the direction in which the cutting edge 34 is formed is set to 4.0 mm. Furthermore, the ultra-hard sintered body 3 of the cutting blade member 32
1 and the high hardness sintered body 30, the bottom surface 2 of the notch 26
The thicknesses T1 and T2 in the direction along the inclination of 6A are set to 1.5 mm and 3.7 mm, respectively.

The chip having such a configuration is mounted on a milling machine as shown in FIG. 5 and used as a rough cutting edge. In the milling machine shown in this figure, a plurality of chip mounting seats 42 are formed at equal intervals along the circumferential direction of the tool main body 41 on the outer periphery of the tip of the tool main body 41 formed in a substantially cylindrical shape. The tip 43 is mounted on the tip mounting seat 42 with the one end face 22 serving as a rake face facing the tool rotation direction, and the cutting blade 34 protruding from the outer peripheral face of the tool.

A recess 44 is formed on the rear side of the tip mounting seat 42 in the tool rotation direction so as to face the tip mounting seat 42. A wedge member 45 is inserted into the recess 44 and fastened by a clamp screw 46. As a result, the tip 43 is pressed against the wall surface of the tip mounting seat 42 on the front side in the tool rotation direction, and is fixed to the tool body 41 by wedges. Reference numeral 47 in the drawing denotes a tip pocket formed on the front side of the tip mounting seat 42 in the tool rotation direction. And the tool body 41
Of the machine tool such as a milling machine by fitting the mounting hole 48 formed at the center of the machine with a bolt or the like, and feeding the workpiece to the workpiece while rotating the milling cutter about its axis O. The workpiece is cut by the cutting blade 34.

At this time, according to the chip having the above-described structure, similarly to the conventional example, the portion where the cutting edge 34 is formed is an ultra-high hardness sintered body 31 such as diamond or CBN having extremely high hardness.
, High wear resistance and good cutting performance can be obtained. Further, the cutting blade member 32 on which the cutting blade 34 is formed has an ultra-hard sintered body 3 only in the vicinity of the cutting blade 34.
1 and the other portion is made of a high-hardness sintered body 30 such as a cemented carbide, so that a relatively expensive ultra-high-hardness sintered body 31 can be made as small as possible and an inexpensive chip can be obtained. Can be provided, and the cost required for the cutting operation can be reduced. Further, by reducing the size of the ultra-hard sintered body 31 in this manner, it is possible to provide a chip that can completely use the ultra-hard sintered body 31 in one cutting, and it is possible to provide re-polishing. Efficient chip management work is not required and labor can be reduced.

According to the chip having the above-described structure, the joining surface 33 of the portion of the high-hardness sintered body 30 and the portion of the ultra-high-hardness sintered body 31 constituting the cutting blade member 32 is connected to the cutting blade 34. The cutting edge 34 is formed because it is formed so as to be parallel to the flank of the chip and the width d in this direction of the joining surface 33 in the chip thickness direction is set to 1.0 mm or more. The ultra-high hardness sintered body 31 can be stably and firmly joined to the high hardness sintered body 30. Accordingly, it is possible to prevent a situation in which the ultra-hard sintered body 31 is separated from the high-hardness sintered body 30 and falls off due to a load acting on the cutting edge 34 during cutting, and the chip can be prevented. It is possible to stabilize the durability of the device itself.

Further, according to the chip having the above-described structure, the joining surface 33 between the ultra-high-hardness sintered body 31 and the high-hardness sintered body 30 is formed parallel to the flank, so that the joining surface 33
Is formed in a direction parallel to the cutting edge 34. For this reason, the shear force acting on the joining surface 33 via the portion of the ultra-hard sintered body 31 due to the load acting on the cutting blade 34 acts uniformly on the joining surface 33. Therefore, it is possible to suppress the occurrence of a situation in which the shearing force is concentrated on a part of the joining surface 33 and this part is broken, and in combination with the above-described effects, the super-hard sintering is performed. The bonding property of the body 31 can be further stabilized and strengthened, and the durability of the chip can be improved.

In the above embodiment, the width W of the joining surface 33 in the direction along the direction in which the cutting edge 34 is formed is 4.0 mm.
And the thickness T1 of the ultra-hard sintered body 31 of the cutting blade member 32.
Is set to 1.5 mm, but the present invention is not limited to these numerical values. However, in order to stabilize the joining property while minimizing the portion of the ultra-high-hardness sintered body 31, the width W of the bonding surface 33 is set to 2.5 mm or more, and 31 thickness T1 is 0.8 ~
It is desirable to set each to about 2.0 mm.

Further, in the above embodiment, as shown in FIG. 5, the case where the present invention is applied to a chip for rough machining by milling has been described, but the present invention is not limited to only such a case. For example, as shown in FIGS. 6 and 7, the present invention can be used for a salary blade tip for finishing. In these figures, the same parts as those in the embodiment shown in FIGS. 1 to 4 are denoted by the same reference numerals. Further, in the embodiment shown in FIGS. 1 to 4, the bottom surface 26 </ b> A of the notch 26 is an inclined surface from the one peripheral surface 24 of the chip body 21 to the one end surface 22.
The bottom surface 26A may be a surface parallel to the end surfaces 22 and 23 as in the present embodiment, and the cutting blade member 32 may be formed in a flat plate shape corresponding to the cutout recess 26.

Next, the effectiveness of the present invention will be demonstrated with reference to experimental examples. In this experiment, the width d of the joining surface 33 in the direction along the chip thickness direction was 1.0 mm, 1.5 mm, 2.5 mm, and 3.0 mm for the Sarai blade tip as shown in FIGS. Were manufactured. These are referred to as Experimental Examples 1, 2, 3, and 4, respectively. As a comparative example, the width d of the bonding surface 33 is 0.8 mm and 0.5 mm.
Chips were manufactured. These are referred to as Comparative Examples 1 and 2, respectively. Then, each of these chips was mounted on a milling machine to perform a cutting process, and the state of the ultra-high hardness sintered body 31 of the cutting blade member 32 at this time was observed. Table 1 shows the results.

However, in the present experimental example and the comparative example, the material of the ultra-high hardness sintered body 31 is CBN, and the cutting conditions are as follows. Cutting conditions Workpiece material: FC25 Cutting speed: 450 m / min Feed per tooth: 0.2 mm Cutting depth: 0.25 mm

[0026]

[Table 1]

From the results shown in Table 1, the width d of the bonding surface is 1.
In Experimental Examples 1 to 4 set to 0 mm or more, no abnormality such as breakage was observed in the portion of the ultra-high hardness sintered body even after the end of the cutting operation. On the other hand, the width d of the joining surface is 1.0 mm
In Comparative Examples 1 and 2, which were set to less than 1, the part of the ultra-high hardness sintered body was broken and dropped from the joint surface with the high hardness sintered body during the cutting operation, and the operation had to be interrupted. Did not.

[0028]

As described above, according to the present invention, the part of the ultra-hard sintered body where the cutting edge is formed can be stably and firmly joined to the joint surface with the high-hardness sintered body. Thus, the durability of the chip can be improved. In addition, since the shearing force acting on the joining surface due to the load acting on the cutting blade uniformly acts on the joining surface, it is necessary to prevent a situation in which this shearing force is concentrated on a part of the joining surface and a break occurs. Becomes possible.
Furthermore, since the bottom of the notch is inclined,
The recessed part can be easily made by polishing the corner of the chip body.
It can be formed, and efficient chip mass production becomes possible.
In addition, part of the load acting on the cutting blade
Shear force acting on the joint surface
To remove the ultra-hard sintered body from the cutting edge member.
It can be avoided reliably.

[Brief description of the drawings]

FIG. 1 is a plan view from one end face 22 side of a chip for rough machining showing one embodiment of the present invention.

FIG. 2 is a side view of the embodiment shown in FIG. 1 from one peripheral surface 24 side.

FIG. 3 is a side view of the embodiment shown in FIG. 1 from the other peripheral surface 25 side.

FIG. 4 is an enlarged plan view of a corner portion C1 of the embodiment shown in FIG.

FIG. 5 is a partially cutaway side view showing an example of a milling machine according to the present invention.

FIG. 6 is a plan view of one end face 22 of a tip for a saray blade showing another embodiment of the present invention.

7 is a side view of the embodiment shown in FIG. 6 from the other peripheral surface 25 side.

FIG. 8 is a plan view showing an example of a conventional chip in which a cutting edge portion is made of an ultra-hard sintered body.

FIG. 9 is a side view of the conventional example shown in FIG.

FIG. 10 is a side view of the conventional example shown in FIG. 8 from the other peripheral surface 6 side.

[Explanation of symbols]

 1,21 Chip body 2,22 One end face (rake face) of chip body 6,24 One peripheral face (flank face) of chip body 8,26 Notch recess 9,30 High hardness sintered body 10,31 Ultra high Hardness sintered body 11, 32 Cutting blade member 12, 34 Cutting blade 33 Joining surface C1 Corner of one end surface of chip body d Width of joining surface 33 in direction along chip thickness direction

────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Katsuhiko Sato Gifu, Anpachi-gun, Kobe-cho, Gifu Prefecture 1528 Nakashinda, Yokoi, Mitsubishi Materials Corporation Gifu Works (72) Inventor Yuichi Kodera, Kobe-cho, Anpachi-gun, Gifu Prefecture 1528 Nakashinda, Yokoi, Mitsubishi Materials Corporation Gifu Works (56) References Japanese Utility Model Showa 64-20202 (JP, U) Japanese Utility Model Showa 60-161501 (JP, U) (58) Fields surveyed (Int .Cl. ⁶ , DB name) B23B 27/14-27/20 B23C 5/16-5/24

Claims (1)

(57) [Claims] 1. A notch recess is formed at a corner of an end face of a chip body formed into a polygonal flat plate shape in a chip thickness direction, and a high-hardness sintered body such as cemented carbide and diamond are formed in the notch recess. And a cutting edge member formed by integrally molding a super-hardened sintered body such as cubic boron nitride in a layered manner, with the portion of the super-hardened sintered body fixed toward the peripheral surface of the chip body, In a throw-away tip having a cutting edge formed on the ultra-high hardness sintered body portion of the cutting blade member facing the corner, the ultra-high hardness sintered body and the high hardness sintered body of the cutting blade member are provided. And the flank of the throw-away tip connected to the cutting edge is formed so as to be parallel, and the width of the joining surface in the direction along the tip thickness direction is 1.0 mm or more , and The bottom surface of the notch recess facing the chip thickness direction
Is connected to the flank of the two ridges sandwiching the corner.
From one edge along the other
A throw-away tip, wherein the tip is gradually inclined toward the end face .