JP2001315021A - Throwaway tip, its manufacturing method, and throwaway type ball end mill - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a throwaway tip having a simple shape, facilitating the working, having a blade with superior roundness accuracy, and highly accurately supported and fixed to a throwaway type ball end mill, provide its manufacturing method, and provide the throwaway type ball end mill having the throwaway tip. SOLUTION: This throwaway tip 1 (50) is formed into an approximately semi-circular disk shape, and the circumferential part 2 of the approximate semi-circular disk 1A (150A) is so constituted as to be inclined to its thickness direction, so that a cutting edge part 3 and a flank 4 are formed in the circumferential part 2.

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 used in a throw-away type ball end mill, a method of manufacturing the same, and a throw-away type ball end mill provided with the throw-away tip.

[0002]

2. Description of the Related Art Conventionally, throw-away type ball end mills have been used for processing free-form surfaces of various industrial dies such as press dies and forging dies. Examples of such a throw-away type ball end mill include, for example, Japanese Utility Model Registration No. 2573120, JP-A-9-225723 and JP-A-11-115.
There is one described in 156624.

[0003] The ball end mill described in Utility Model Registration No. 2573120 discloses a ball end mill in which two or more indexable inserts mounted at the axial end of a tool main body have inner peripheral ends at the ends of the respective arc-shaped cutting edges. It is provided with a configuration arranged so as to be separated from the axis of the tool main body. With this configuration, when viewed from the bottom in the axial direction of the tool main body, the diameter of the tool main body is 0.1 to 0.1 mm around the axis of the tool main body.
A 0.5 mm circular arc locus is drawn.

A ball end mill described in Japanese Patent Application Laid-Open No. 9-225723 has a structure in which a throw-away tip is fixed to a tip seat at a tip end portion of a tool body, and a seat on the rotation center side of the tip seat is provided. The side surface and the inner side surface of the throw-away tip supported by the surface are provided substantially parallel to the rotation center axis and provided at a position replaced from the rotation center to the outer peripheral side, the tip side of the throw-away tip is closer to the rotation center than the seat side It is provided with a configuration in which the cutting edge portion is inserted so as to bring the R portion cutting blade portion near the center of rotation. This ball end mill is
The configuration in which the tips of the arc portions of the two throw-away tips overlap each other has an advantage that the rigidity of the tool body can be increased and the machining accuracy can be improved.

In the ball end mill described in Japanese Patent Application Laid-Open No. H11-156624, two indexable inserts each having a cutting edge having a substantially 1/4 arc shape are provided at the tip of the tool body. It has a configuration in which it is mounted facing each other across the axis. In this ball end mill, the tip of each of the cutting blades is disposed so that the tip of the cutting blade is positioned at the center of rotation of the tool body, and the rotation trajectories around the axis coincide with each other. A configuration is provided in which the end side is provided so as to extend to the rear end side in the axial direction from the rear end position of the other cutting edge portion. The ball end mill has an advantage that damage to the chips can be prevented because a large cutting load acting on the center of rotation of the tool can be dispersed by the pair of chips.

[0006]

However, the throw-away insert of the ball end mill described in the above-mentioned publication has a complicated shape, is difficult to machine, takes much time and effort to manufacture, and the R accuracy of the cutting edge is low. There is a risk of lowering.

[0007] In particular, utility model registration No. 2573120
In the throw-away insert of the ball end mill described in Japanese Patent Application Laid-Open Publication No. H11-260, the respective arc-shaped cutting edge portions are disposed so as to be separated from the axis of the tool body (that is, the tip of each cutting edge portion). With a gap between them)
Therefore, there is a possibility that the supporting accuracy of this portion may not be sufficiently obtained.

SUMMARY OF THE INVENTION An object of the present invention is to solve such a conventional problem. The present invention has a simple shape, is easy to process, and has excellent R accuracy of the cutting edge portion. It is an object of the present invention to provide a throwaway tip that is often supported and fixed to a throwaway ball end mill.

Another object of the present invention is to provide a method for manufacturing a throw-away tip according to the present invention, and a throw-away type ball end mill provided with the throw-away tip.

[0010]

In order to achieve this object, the present invention relates to a throw-away tip used in a throw-away type ball end mill, which is formed in a substantially semi-disc shape. Is configured to be inclined with respect to the thickness direction thereof, thereby providing a throwaway tip having a cutting edge portion and a flank formed on the circumferential portion.

The indexable insert having this configuration is simple in shape, for example, is formed by dividing a substantially disk-shaped material into two parts, and is simple in processing, and is excellent in R accuracy. Can be easily obtained. In addition, since the circumferential portion of the substantially semi-circular plate forms the cutting edge portion and the flank, the dimensional accuracy of the entire circumferential portion is improved. Therefore, the mounting accuracy of the throw-away tip to the mounting seat of the throw-away type ball end mill is improved.

[0012] At one end of the straight portion of the substantially semi-circular plate, a projecting piece projecting on an extension of an arc constituting the circumferential portion can be formed.

With this configuration, in addition to the above advantages, for example, if two indexable inserts are mounted point-symmetrically with respect to the center of rotation, the effective number of cutting edges at the substantially central portion becomes two. And the load acting on this part is halved. Accordingly, the machining efficiency can be increased by increasing the feed per rotation.

The indexable insert according to the present invention has a thickness gradually reduced on the substantially semi-disc surface on which the cutting edge is formed, from the cutting edge toward the center of the substantially semi-disc. An inclined scooping surface can be formed along the cutting blade portion. By doing so, the cutting performance can be further improved in addition to the above advantages.

Further, the indexable insert according to the present invention may include a screw insertion hole penetrating from a substantially semi-disc surface on which the cutting edge portion is formed to a surface opposed to this surface.

Still further, according to the present invention, a substantially disk-shaped material in which an outer peripheral portion is processed to form an inclined surface, and a cutting edge portion and a flank are formed in the outer peripheral portion is divided into two in the diameter direction. And a method of manufacturing a throwaway tip for manufacturing two throwaway tips.

Further, according to the present invention, after a substantially semi-disc-shaped material is attached to a jig, a circumferential portion of the material is worked so as to be inclined with respect to a thickness direction thereof. And a method of manufacturing a throwaway tip that forms a cutting edge portion and a flank.

According to these manufacturing methods, it is possible to easily obtain a throw-away tip which is excellent in the R accuracy of the cutting edge portion and can be supported and fixed to the throw-away type ball end mill with high accuracy by a simple process.

Further, the present invention is a throw-away type ball end mill comprising the above-described throw-away tip according to the present invention mounted on a mounting seat formed at a tip end portion of a tool body which is rotationally driven. The seat provides a throw-away type ball end mill having a contact surface with which a base end portion of the throw-away tip comes into contact.

In the throw-away type ball end mill having this configuration, the cutting edge portion and the flank are also formed at the base end of the throw-away tip, and the dimensional accuracy is excellent. , High contact accuracy can be obtained. Therefore, the mounting accuracy of the indexable insert is improved, and the reliability of the indexable ball end mill is improved.

Further, the present invention is a throw-away type ball end mill comprising two throw-away chips each having the above-mentioned protruding piece attached to a mounting seat formed at a tip end portion of a rotary-driven tool body. At the tip of the tool body, the projections of each of the throw-away tips are arranged so as to overlap each other, and the mounting seat has a contact surface with which a base end portion of each of the throw-away tips abuts. It is intended to provide an away type ball end mill.

In the throw-away type ball end mill having this configuration, the number of effective cutting edges of the cutting edge portion disposed substantially at the center of the tip becomes two, and the load acting on this portion is reduced by half. Accordingly, the machining efficiency can be increased by increasing the feed per rotation.

[0023] The contact surface may have a shape corresponding to a cutting edge portion formed at a base end portion of the indexable insert.

Further, the contact surface may have a shape corresponding to a flank formed at a base end portion of the indexable insert.

Further, a recess is formed in the contact surface,
The base end portion of the throw-away tip may be configured to contact the contact surface on both sides of the recess.

According to the present invention, there is also provided a throw-away type ball end mill comprising the above-described throw-away tip according to the present invention mounted on a mounting seat formed at a tip end portion of a tool body which is driven to rotate. The outer diameter of the neck portion on which the contact surface of the tool body is formed is made smaller than the maximum rotation outer diameter of the cutting blade portion of the tip, and the base end side of the cutting blade portion from the maximum rotation outer diameter position is the neck. An object of the present invention is to provide a throw-away type ball end mill protruding from a portion.

In the throw-away type ball end mill having this configuration, the base end side of the cutting edge portion of the throw-away tip can be effectively used as the cutting edge portion, and the cutting range can be widened. Can be.

[0028]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a throwaway tip according to a preferred embodiment of the present invention and a throwaway ball end mill to which the throwaway tip is attached will be described with reference to the drawings. (Embodiment 1) FIG. 1 is a front view of a throw-away type ball end mill according to Embodiment 1, FIG. 2 is a side view showing a tip portion of the throw-away type ball end mill according to Embodiment 1, and FIG. Is a side view of the throw-away tip according to Embodiment 1, FIG. 4 is a plan view of the throw-away tip according to Embodiment 1, and FIG.
FIG. 6 is a cross-sectional view taken along the line V. FIG. 6 is a perspective view showing a tip end portion of the tool body of the throw-away ball end mill according to the first embodiment.

In the first embodiment, the side of the throw-away type ball end mill to which the throw-away tip is attached will be referred to as the "tip", and the opposite side (the opposite side) will be referred to as the "base end".

As shown in FIGS. 1 to 5, the throw-away tip 1 according to the first embodiment includes a substantially semi-disc 1A formed in a substantially semi-disc shape. The circumferential portion 2 of the substantially semi-circular plate 1A is inclined with respect to the thickness direction, thereby forming the cutting edge 3 and the flank 4. That is, the cutting edge 3 and the flank 4 are formed over the entire circumference 2 of the substantially semi-circular plate 1A. Reference numeral 8 indicates a straight line portion of the substantially semi-circular plate 1A.

In addition, near the circumferential portion 2 on the surface of the substantially semi-circular plate 1A on which the cutting edge portion 3 is formed (hereinafter, this surface is referred to as "upper surface"), the cutting edge portion 3 is provided. A scooping surface 5 is formed along the cutting edge portion 3 so as to be inclined so that the thickness of the substantially semi-circular plate 1A gradually decreases toward a substantially center O (see FIG. 4) that draws a substantially semi-circular arc from I have. The upper surface and the lower surface of the substantially semi-circular plate 1A are formed substantially in parallel.

As will be described in detail later, a screw hole 7 through which the screw 6 for fixing the throw-away tip 1 to the tool body 11 of the throw-away type ball end mill 10 is formed in the substantially semi-circular plate 1A. At two locations.

Throwaway ball end mill 10
Is provided with the above-mentioned throw-away tip 1 and a tool body 11 which is mounted on the tip of the throw-away tip 1 and driven to rotate.

At the tip of the tool body 11, mounting portions 12A and 12B for mounting the throw-away tip 1 are provided.
They are formed at positions displaced from each other by 180 degrees with respect to the axis of the tool body 11. The attachment portions 12A and 12B are formed in a shape corresponding to the shape of the throw-away tip 1. In particular, as shown in FIG. 2, the two throw-away tips 1 are overlapped on the distal side and the base end side. They are arranged so as to be separated from each other at an angle θ.

Specifically, the straight portion 8 of the throw-away tip 1 is provided on the tool body axis side of the mounting portions 12A and 12B.
Are formed, and the straight part contact surfaces 16A and 16B are formed.
At the base ends of the mounting portions 12A and 12B, mounting seats 13A and 13B having contact surfaces 19A and 19B with which the base end of the throw-away tip 1 abuts are formed. The mounting seats 13 </ b> A and 13 </ b> B have shapes corresponding to the cutting edge 3 and the flank 4 formed at the base end of the indexable insert 1. Concave portions 14A and 14B are formed substantially at the center of the mounting seats 13A and 13B, and the base end of the throw-away tip 1 is
Both sides of A are in contact with the contact surfaces 19A and 19B. Furthermore, the straight portion contact surfaces 16A and 16B
And the mounting seats 13A and 13B, escapes 15A and 15B are formed to prevent the base end corner of the throw-away tip 1 from contacting. The attachment parts 12A and 12B have a throw-away tip 1
At the positions corresponding to the two screw holes 7, these screw holes 7
And a screw hole 17 that can communicate with it.

As described above, since the two throw-away tips 1 are disposed with their tips overlapping each other, the throw-away type ball end mill 10 has an effective number of cutting edges 3 of the cutting edge portion 3 at the substantially axial center tip. It becomes two. Therefore, the load acting on this portion is reduced by half, and the feed per rotation can be increased to increase the machining efficiency.

The outer diameter r of the neck portion 18 formed continuously on the base end side of the attachment portions 12A and 12B of the tool body 11
₁ (see FIG. 2) is the cutting edge 3 of the indexable insert 1
Is smaller than the maximum rotation outer diameter r ₂ (see FIG. 2). As a result, a portion of the cutting edge portion 3 located on the base end side of the maximum rotation outer diameter position projects (extends) outward from the neck portion 18, so that this portion is also substantially a cutting edge portion. 3 can be used effectively, and the cutting range can be widened.

When attaching the indexable insert 1 to the tool body 11, the mounting portions 12A and 12A
The indexable inserts 1 are respectively arranged in 2B, and the screws 6 are screwed into the screw holes 7 and 17 and fixed. At this time, the indexable insert 1 is mainly positioned by the mounting seats 13A and 13B. However, the cutting blade portion 3 and the flank 4 are also formed at a portion where the indexable insert 1 comes into contact with the mounting seats 13A and 13B. Therefore, this portion is also formed with excellent dimensional accuracy. Therefore, the mounting accuracy of the indexable insert 1 can be improved.

Next, a method for manufacturing the throw-away tip according to the first embodiment will be described with reference to the drawings.

FIG. 7 is a plan view showing a material for manufacturing the indexable insert according to Embodiment 1, and FIG.
It is a side view which shows the process of processing the circumference part of the raw material shown in FIG.

As shown in FIG. 7, the material 100 has a disk shape whose upper surface and lower surface are substantially parallel to each other, and has four screw holes 7 through which the screws 6 pass. The screw hole 7 is used to insert the completed indexable insert 1 into the tool body 1
It is formed at a position that functions as a screw hole 7 through which the screw 6 passes when screwed to the first mounting portions 12A and 12B. Further, a center 105A (hereinafter, referred to as a center) for supporting a rotation center of a jig 102 described later is provided at a central portion of the material 100.
A fitting hole 103 into which the tip of the “center” is fitted is formed.

The scooping surface 115 (corresponding to the scooping surface 5 of the obtained throw-away chip 1) is provided on the upper surface of the material 100 in the vicinity of the circumferential portion 110 along the circumferential portion 110.
The scooping surface 115 may be formed before or after the finishing of the circumferential portion 110 of the raw material 100 described in detail below.

First, the material 100 is mounted on a jig 102 such as a cylindrical polishing machine shown in FIG. This jig 1
02 is a mounting surface 10 on one side of which the material 100 is mounted.
In the mounting surface 104, screw holes 106 for screwing the screws 6 are formed at positions corresponding to the four screw holes 7 of the arranged material 100. In addition, a fitting hole 108 is formed in the side surface 107 opposite to the mounting surface 104, in which the tip of the center 105B fits.

After the material 100 is screwed to the jig 102, the tip of the center 105 A is inserted into the fitting hole 103 of the material 100.
And the tip of the center 105B is fitted into the fitting hole 108 of the jig 102. Next, the centers 105A and 1
The jig 102 is rotated with reference to 05B.

The circumferential portion 11 of the rotating material 100
0 is finished with a grindstone 101 and the circumferential portion 1 of the material 100
10, an inclined surface inclined in the thickness direction is formed, thereby forming the cutting edge portion 111 and the flank surface 112.
As described above, the cutting edge 111
And the flank 112 can be formed. In addition, since the material 100 itself has a disk shape, the cutting edge portion 111 having excellent R accuracy can be easily formed.

The material 100 can be made of, for example, a cemented carbide. In this case, the material 100 is
In a completely sintered state, the circumferential portion 11 is
0 can be machined, and also in this case, the R accuracy of the cutting blade 111 can be easily improved.

After finishing the peripheral portion 110 of the material 100 and forming the cutting edge 111 and the flank 112, the material 100 removed from the jig 102 is, for example,
It is cut along the diameter by a wire cutting machine or the like and divided into two. Thus, two indexable chips 1 are obtained. Here, the circumferential portion 110, the cutting edge portion 111, and the flank surface 112 correspond to the circumferential portion 2, the cutting edge portion 3, and the flank surface 4 of the indexable insert 1 obtained by division, respectively.

The material 100 may be divided into two parts by cutting on the diameter. As shown in FIG. 9, the material 100 is cut on a line L slightly separated from the diameter and parallel to the diameter. May be divided.

As described above, since the raw material 100 has a disk shape whose upper and lower surfaces are substantially parallel to each other, it is easy to manufacture, and the cutting blade 111 and the flank 112 are also formed by simple finishing as described above. Can be formed. In addition, since the indexable insert 1 according to the first embodiment has a substantially semi-disc shape, the material 100 on which the cutting edge 111 and the flank 112 are formed can be divided into two by a simple process. Obtainable.

In the indexable insert 1 according to the first embodiment, after the material 100 is divided into two parts, the peripheral portion may be finished. In this case, a jig 122 such as a cylindrical grinder shown in FIG.
And 100B, the circumferential portions 110A and 110B may be finished using the grindstone 101.

FIG. 10A is a side view of the jig 122, and FIG. 10B is a perspective view of the jig 122. FIG.
In the jig 122 shown in (1) and (2), one side surface of a substantially cylindrical main body 123 is a mounting surface 124 on which the raw materials 100A and 100B are mounted. At a portion corresponding to the diameter of the mounting surface 124, a contact portion 126 with which the linear portions 125A and 125B of the raw materials 100A and 100B abut is formed. At a substantially central portion of the contact portion 126, a cylindrical convex portion 127 having a fitting hole 103 into which the tip of the center 105A is fitted is formed. Further, four screw holes 106 similar to the above are formed in the mounting surface 124, and a fitting hole 108 similar to the above is formed in the side surface 128 opposite to the mounting surface 124.

As shown in FIG. 11, the materials 100A and 100B are screwed to the jig 122 so that the materials 100A and 100B are arranged between the mounting surface 124 and the cylindrical protrusion 127. The center portion 105B is fitted into the fitting hole 108 formed in the side surface 128 by fitting into the fitting hole 103 of the convex portion 127. Next, the center 105
The jig 122 is rotated based on A and 105B.

The rotating materials 100A and 100
B at circumferential portions 110A and 110B in the same manner as above.
01 to obtain the indexable insert 1.
Even if this method is used, the cutting edge 3 and the flank 4 can be formed by simple finishing. In addition, also in the case of this method, the formation of the scooping surface 5 can be performed at a desired time.

In the first embodiment, the case where the tips of the throw-away tips 1 are arranged in an overlapping state has been described. However, the present invention is not limited to this, and the tips of the throw-away tips 1 are shown in FIG. As described above, it may be in a contact state.

In the first embodiment, the case where the throw-away tip 1 is fixed to the mounting portions 12A and 12B of the tool body 11 using two screws 6 for one throw-away tip 1 has been described. Not limited to this,
The number of screws 6 for fixing the throw-away tip 1 may be arbitrarily determined, such as one or three or more.

Further, in the first embodiment, the case where the scooping surface 5 is positively formed by forming the grooves as shown in FIG. 5 has been described.
As shown in FIG. 5, even without forming the above-described groove on the upper surface of the substantially semi-circular plate 1A, the vicinity of the cutting edge 3 on the upper surface of the substantially semi-circular plate 1A
It can serve as the scooping surface 5A. Also,
When a scooping surface is to be formed actively by forming grooves or the like, FIG.
As shown in FIG. 8 (2), the shape of the scooping surface 5B having a semicircular cross section may be arbitrarily determined.

In the first embodiment, the mounting seat 1
Although the case where the concave portions 14A and 14B are formed in 3A and 13B has been described, the present invention is not limited thereto.
4B is not necessarily provided. (Embodiment 2) Next, Embodiment 2 according to the present invention will be described with reference to the drawings.

FIG. 13 is a front view of a throw-away type ball end mill according to Embodiment 2, FIG. 14 is a side view showing a tip portion of the throw-away type ball end mill according to Embodiment 2, and FIG. FIG. 16 is a plan view of a throw away tip according to Embodiment 2, and FIG. 16 is a perspective view showing a tip end portion of a tool body of a throw away type ball end mill according to Embodiment 2.

In the second embodiment, the same members as those described in the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIGS. 13 to 15, the difference between the throw away tip 50 according to the second embodiment and the throw away tip 1 according to the first embodiment is that the straight portion 8 of the substantially semi-circular plate 50A is provided. Is formed at one end thereof with a protruding piece 59 protruding on an extension of an arc forming the substantially semicircular plate 50A circumferential portion 2.

That is, the throw-away tip 50 according to the second embodiment has a substantially semi-disc shape.
0A, a protruding piece 59 is formed at one end of the linear portion 8 of the substantially semi-circular plate 50A so as to protrude on an extension of an arc forming the circumferential portion 2 of the substantially semi-circular plate 50A. The circumferential portion 2 including the projecting piece 59 is inclined with respect to the thickness direction, so that the cutting blade 3 and the flank 4 are formed over the entire circumferential portion 2 including the projecting piece 59. Have been. In addition, the substantially semi-circular plate 50
A scooping surface 5 is formed along the cutting edge 3 in the vicinity of the circumferential portion 2 on the upper surface of A. Further, a screw hole 7 through which a screw 6 for fixing the throw-away tip 50 to the tool body 151 of the throw-away ball end mill 150, which will be described in detail later, penetrates the substantially semi-circular plate 50A, and penetrates one place in the thickness direction. Is formed. The tip 59P of the protruding piece 59
The corner 50P on the base end side of the throw-away tip 50 may be rounded.

Throw-away ball end mill 150
Is configured to include the above-described throw-away tip 50 and a tool body 151 that is mounted on the tip of the throw-away tip 50 and rotationally driven.

At the tip of the tool body 151, mounting portions 152A and 152 for mounting the throw-away tip 1 are provided.
B are formed at positions displaced from each other by 180 degrees with respect to the axis of the tool main body 151. These mounting portions 152A and 1
52B is formed in a shape corresponding to the shape of the throw-away tip 50. In particular, as shown in FIG. 14, the two throw-away tips 50 overlap the protruding pieces 59, and the straight portion 8 is Are arranged so as to be substantially parallel to the axis.

Specifically, the mounting portions 152A and 152B
The straight portion contact surfaces 156A and 156B with which the straight portion 8 of the throw-away tip 50 abuts on the tool body axis center side.
Are formed substantially parallel to the axis of the tool body,
At the proximal end of 2A and 152B, a throwaway tip 5
Attachment seats 153A and 153B having contact surfaces 159A and 159B with which the base end portion of 0 is in contact are formed. The mounting seats 153A and 153B are provided on the cutting edge 3 and the flank 4 formed at the base end of the throw-away tip 50.
It has a shape corresponding to. In addition, concave portions 14A and 14B are formed at substantially the center portions of the mounting seats 153A and 153B, and reliefs 15A and 15B are formed at intersections of the straight portion contact surfaces 156A and 156B and the mounting seats 153A and 153B. ing. Further, screw holes 17 that can communicate with the screw holes 7 are formed in the mounting portions 152A and 152B at positions corresponding to the screw holes 7 of the throw-away tip 50 disposed here.

As described above, in the second embodiment as well,
Of the throw-away tips 50,
9 are arranged in an overlapping manner. Therefore, in the throw-away type ball end mill 150, since the number of effective blades of the cutting blade portion 3 becomes approximately two at the substantially axial center end portion, the load acting on this portion is reduced by half, and the feed per rotation is increased to increase the processing. Efficiency can be improved.

When the indexable insert 50 is to be mounted on the tool body 151, the mounting portion 152 of the tool body 151 is mounted.
A throw-away tip 50 is arranged at each of A and 152B, and the screw 6 is screwed into the screw holes 7 and 17 and fixed.
At this time, the mounting accuracy of the throw-away tip 50 is improved as in the first embodiment.

The manufacture of the indexable insert according to the second embodiment is performed according to the manufacturing method described in the first embodiment. When the material 100 is divided into two parts, as shown in FIG. 59 are formed. The processing for adding R to the distal end portion 59P of the protruding piece 59 and the corner portion 50P on the base end side of the throw-away tip 50 is performed using a material 10
It may be performed at the time of division of 0, or may be performed after the division.

As described above, the indexable insert 50 according to the second embodiment is also easy to manufacture, as in the first embodiment, and the R accuracy of the cutting blade 3 can be easily improved. Good throw-away ball end mill 150
Can be mounted on

In the second embodiment, the case where the throw-away tip 50 is fixed to the mounting portions 152A and 152B of the tool body 151 using one screw 6 with respect to one throw-away tip 50 has been described. The screw 6 for fixing the throw-away tip 50 is not limited to this.
May be plural.

[0070]

As described above, the indexable insert according to the present invention is formed in a substantially semi-disc shape, and the circumference of the substantially semi-disc is inclined with respect to its thickness direction. Since the cutting edge and the flank are formed on the circumferential portion, a cutting edge with excellent R accuracy can be easily obtained by simple processing. In addition, since the circumferential portion of the substantially semi-circular plate forms the cutting edge portion and the flank, the dimensional accuracy of the entire circumferential portion can be improved. Therefore, it is possible to provide a reliable throwaway tip in which the accuracy of attaching the throwaway tip to the mounting seat of the throwaway ball end mill is improved.

Further, according to the method of manufacturing a throw away tip according to the present invention, the above described throw away tip can be obtained by using a simple method of dividing a substantially disc-shaped material into two.

Further, in the throw-away type ball end mill according to the present invention, since the above-mentioned throw-away tip is mounted, the accuracy of mounting the throw-away tip is improved, and the reliability of the throw-away type ball end mill is improved. be able to.

[Brief description of the drawings]

FIG. 1 is a front view of a throw-away type ball end mill according to Embodiment 1 of the present invention.

FIG. 2 is a side view showing a tip portion of the throw-away type ball end mill according to Embodiment 1 of the present invention.

FIG. 3 is a side view of the throw-away tip according to Embodiment 1 of the present invention.

FIG. 4 is a plan view of the throw-away tip according to Embodiment 1 of the present invention.

FIG. 5 is a sectional view taken along line VV shown in FIG.

FIG. 6 is a perspective view showing a tip end portion of the tool body of the throw-away type ball end mill according to the first embodiment of the present invention.

FIG. 7 is a plan view showing a material for manufacturing the throw-away tip according to Embodiment 1 of the present invention.

FIG. 8 is a side view showing a processing step of a circumferential portion of the material shown in FIG. 7;

FIG. 9 is a plan view showing a processing step of a material according to another embodiment of the present invention.

FIG. 10 (1) is a side view of a jig for processing a material according to another embodiment of the present invention. (2) is a perspective view of a jig for processing a material according to another embodiment of the present invention.

FIG. 11 is a side view showing a process of processing a circumferential portion of a material according to another embodiment of the present invention.

FIG. 12 is a side view showing a tip portion of a throw-away type ball end mill according to another embodiment of the present invention.

FIG. 13 is a front view of a throw-away type ball end mill according to Embodiment 2 of the present invention.

FIG. 14 is a side view showing a tip portion of a throw-away type ball end mill according to Embodiment 2 of the present invention.

FIG. 15 is a plan view of a throw-away tip according to Embodiment 2 of the present invention.

FIG. 16 is a perspective view showing a tip end portion of a tool main body of a throw-away type ball end mill according to Embodiment 2 of the present invention.

FIG. 17 is a plan view showing a processing step of a material according to another embodiment of the present invention.

FIG. 18 is a sectional view of a throw-away tip according to another embodiment of the present invention. (2) is a sectional view of a throw-away tip according to another embodiment of the present invention.

[Explanation of symbols]

 1, 50 throw-away inserts 1A, 150A substantially semi-circular plate 2 circumferential part 3 cutting edge part 4 flank 5, 5, 5A, 5B scooping surface 6 screw 7, 17 screw hole 8 linear part 10, 150 throw-away ball end mill 11 , 151 Tool body 12A, 12B, 152A, 152B Mounting part 13A, 13B, 153A, 153B Mounting seat 18 Neck part 19A, 19B, 159A, 159B Contact surface 100 Material

Claims (14)

[Claims] 1. A throw-away tip used in a throw-away type ball end mill, wherein the tip is formed in a substantially semi-circular shape, and a circumferential portion of the semi-circular shape is inclined with respect to a thickness direction thereof. And a cutaway portion having a cutting edge portion and a flank formed on the circumferential portion. 2. The indexable insert according to claim 1, wherein a projecting piece is formed at one end of the linear portion of the substantially semi-circular plate and protrudes on an extension of an arc forming the circumferential portion. 3. A scooping surface inclined on the substantially semi-disc surface on which the cutting edge portion is formed, so that the scooping surface gradually decreases in thickness from the cutting edge portion toward the center of the substantially semi-disc. The indexable insert according to claim 1, wherein the insert is formed along the cutting edge. 4. A scooping surface which is inclined on the substantially semi-disc surface on which the cutting edge portion is formed so as to gradually decrease in thickness from the cutting edge portion toward the center of the substantially semi-disc, 3. The indexable insert according to claim 2, wherein the insert is formed along the cutting edge. 5. The indexable insert according to claim 1, further comprising a screw insertion hole penetrating from a substantially semi-disc surface on which the cutting edge portion is formed to a surface opposite to the semi-disc surface. 6. The indexable insert according to claim 2, further comprising a screw insertion hole penetrating from a substantially semi-disc surface on which the cutting edge portion is formed to a surface opposite to the semi-disc surface. 7. A substantially disk-shaped material in which an outer peripheral portion is processed to form an inclined surface, and a cutting edge portion and a flank are formed in the outer peripheral portion, are divided into two in the diameter direction, and two throws are formed. A method for manufacturing a throwaway tip for producing an away tip. 8. After attaching a substantially semi-disc-shaped material to a jig,
A method of manufacturing a throwaway tip, wherein a circumferential portion of the material is processed so as to be inclined with respect to a thickness direction thereof, thereby forming a cutting edge portion and a flank on the circumferential portion. 9. A throw-away type ball end mill comprising a throw-away tip according to any one of claims 1 to 6 mounted on a mounting seat formed at a tip end of a tool body that is rotationally driven. The throw-away type ball end mill, wherein the mounting seat has a contact surface with which a base end portion of the throw-away tip comes into contact. 10. A throw having two throw-away tips according to claim 2, attached to a mounting seat formed at a tip end portion of a tool body that is rotationally driven. An away type ball end mill, wherein a protrusion of each of the throw away tips is disposed so as to overlap with a tip of the tool body, and the mounting seat is in contact with a base end portion of each of the throw away tips. A throw-away type ball end mill with a contact surface. 11. The throw-away type ball end mill according to claim 9, wherein the contact surface has a shape corresponding to a cutting edge formed at a base end portion of the throw-away tip. 12. The throw-away type ball end mill according to claim 9, wherein the contact surface has a shape corresponding to a flank formed at a base end portion of the throw-away tip. 13. The contact surface according to claim 9, wherein a recess is formed in the contact surface, and a base end portion of the throw-away tip contacts the contact surface on both sides of the recess. The throw-away ball end mill as described. 14. A throw-away type ball end mill comprising a throw-away tip according to any one of claims 1 to 6 mounted on a mounting seat formed at a distal end portion of a tool body which is driven to rotate. The outer diameter of the neck portion on which the contact surface of the tool body is formed is made smaller than the maximum rotation outer diameter of the cutting edge portion of the throw-away tip, and the outer diameter of the cutting portion is set to be smaller than the maximum rotation outer diameter position. A throw-away type ball end mill having an end protruding from the neck portion.