JPH0847809A - Throw-away type rolling tool - Google Patents

Abstract

(57) [Summary] [Purpose] To improve the chip life by using a conventional throw-away chip. [Structure] A rectangular plate-shaped negative tip 10 is provided on the outer peripheral portion of the tip of a cutter body 7 of a front milling cutter 6, a first throw-away tip 10A and a second throw-away tip 1.
As 0B, they are mounted alternately at equal intervals in the rotation direction. First
The corner angle of the outer peripheral side main cutting edge 14B of the second tip 10B is set to be larger than the corner angle of the outer peripheral side main cutting edge 14A of the tip 10A. The two main cutting edges 14A and 14B intersect in the cutting region of the work material when viewed in the rotational direction, and the tip 10B has a longer blade length from the intersection p to the tip side. The cutting is performed at the intersection p of the front cutting edge 15A of the tip 10A and the area of the blade length a of the main cutting edge 14A and the main cutting edge 14B of the tip 10B.
To the proximal region.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a throw-away type milling tool such as a face mill or end mill having a plurality of throw-away inserts.

[0002]

2. Description of the Related Art As an example of this type of rolling tool, there is a face milling machine as shown in FIG. In the partial vertical cross-sectional view of the front milling cutter shown in FIG. 4, a plurality of concave grooves forming the chip seats 3 are formed at predetermined intervals on the outer peripheral portion of the front end of the cutter body 2 of the front milling cutter 1. A throw-away tip 4 having a substantially rectangular plate shape is attached to each tip seat 3 as a vertical blade, and is fixed by a screw or the like not shown. The throw-away tip 4 has an upper surface (and a lower surface) forming a parallel plane.
Each long side and each ridge side in the plate thickness direction are respectively formed as cutting edges, and in the mounted state, the long side of the corner c is located on the tip outer peripheral surface of the cutter body 2 to form the main cutting edge 4a. The ridge side in the plate thickness direction is located on the front side of the front end to form the front cutting edge 4b. Then, the plurality of throw-away tips 4 have a main cutting edge 4a and a front cutting edge 4b in the rotation direction of the cutter body 2.
They are fixed in the same posture so that and overlap. Further, the throw-away tips 4 are set to have the same corner angle by the main cutting edge 4a of the corner c in the mounted state. Then, at the time of cutting, at the corner c located on the outer periphery of the tip of each tip 4 mounted on the cutter body 2, the main cutting edge 4a located on the outer peripheral side and the cutting portion of the front cutting edge 4b located on the front side are formed. The work material is cut,
It is designed to be fed horizontally and vertically.

[0003]

However, the face milling cutter 1 using the throw-away tip 4 as described above.
In the case of, when the tip 4 is a positive tip in which the cutting edge 4a forming the long side thereof has a sharp cutting edge angle, only two corners can be used, and when the cutting edge angle is 90 degrees, it is a negative tip. However, since only four corners can be used on the upper surface and the lower surface, the chip life is relatively short. Moreover, when the negative tip is used, although four corners can be used, there is a drawback that the sharpness is inferior because it has to be mounted on a so-called double negative in which both the axial rake angle and the radial rake angle are negative.

In view of the above-mentioned circumstances, the present invention uses a throw-away insert having the same blade shape, and is capable of substantially double the number of corners for cutting as compared with the conventional one.
It is an object of the present invention to provide a throw-away type milling tool capable of significantly increasing the insert life.

[0005]

A throw-away type rolling tool according to the present invention comprises a throw-away type cutting tool in which a plurality of throw-away tips each having a cutting edge are mounted on the outer peripheral portion of the tip of a cutter body. In the tool, the plurality of throw-away tips are respectively arranged as a first throw-away tip and a second throw-away tip whose cutting edge corner angles are different from each other, and when viewed in the rotation direction of the cutter body, the first throw-away tips and The outer peripheral cutting edges of the second throw-away tip are configured to intersect each other in the cutting region.

Further, the first throw-away tip and the second throw-away tip are arranged alternately and in the same number in the rotation direction of the cutter body. The throw-away tip is a negative type tip with a cutting edge angle of about 90 degrees, and one of the first and second throw-away tips with the larger cutting edge corner angle is installed so that the axial rake angle is positive. ing. Further, one of the first and second throw-away tips, which has a larger cutting edge corner angle, is characterized in that the front cutting edge is located closer to the base end side than the front cutting edge of the other tip. or,
The blade length on the tip side from the intersection of the outer peripheral cutting edges of the first and second throw-away tips is set longer for the tip having a larger corner angle. Further, the cutting tool may be a face mill and the throw-away tip may have a substantially rectangular plate shape.

[0007]

In the above-described rolling tool equipped with the throw-away tip, if the tip with the smaller corner angle of the cutting edge is the first throw-away tip, the work material is cut frontally with the first throw-away tip. Cutting is performed in the area from the tip side of the outer peripheral side main cutting edge to the intersection, and in the second throw-away tip, cutting is performed in the area from the intersection of the outer peripheral side main cutting edge to the base end side. Even if the cutting edge of the first or second throw-away tip is missing, this tip can be used at the same corner as the second or first throw-away tip, so the number of usable corners is doubled. , The chip life is improved.

Since the first and second throw-away tips are arranged alternately and in the same number, the cutting characteristics are stabilized. Since the throw-away tip is a negative type tip, the number of corners that can be used is substantially doubled compared to the positive tip, and the tip with a larger cutting edge corner angle can make the axial rake angle positive. The sharpness is improved because it can be done. Further, the tip having a larger cutting edge corner angle does not participate in cutting on the tip side because the front cutting edge is located closer to the base end side than the other front cutting edge. When the first throw-away tip and the second throw-away tip are exchanged for use, the blade length of the unused portion during the previous use can be used as the used portion of each outer peripheral side cutting blade. Further, by laterally feeding the front milling cutter, the work material is cut as a two-step inclined surface to perform flat cutting.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described below with reference to FIGS.
This will be described below. 1 is a partial longitudinal sectional view of a front milling cutter according to this embodiment, FIG. 2 is a side view of a first throw-away tip portion of the front milling cutter shown in FIG. 1, and FIG. 3 is a second throw-away tip of the front milling cutter shown in FIG. It is a side view of a part. In the front milling cutter 6 shown in FIG. 1, first tip seats 8 and second tip seats 9 each having a substantially rectangular shape in a side view and having a groove shape are alternately formed along the outer periphery of the tip of the cutter body 7 at substantially equal intervals. Moreover, the first tip seat 8 is formed on the outer peripheral portion of the tip of the cutter body 7 so as to be inclined toward the outer periphery of the axis O by a predetermined angle α, and the second tip seat 9 is formed with respect to the axis O. It is formed to be inclined toward the outer peripheral side by a larger predetermined angle β. Therefore, the outer peripheral surface of the tip of the cutter body 7 is
At the positions of the first and second chip seats 8 and 9, the convex and concave shapes are alternately formed in the circumferential direction.

These first and second tip seats 8 and 9 are
The throw-away tip 10 in the shape of a substantially rectangular plate is mounted so that its longitudinal direction is the same as that of each tip seat, and is fixed to the cutter body 7 by a clamp member such as a screw or a wedge member (not shown). Moreover, in the cutter body 7, a first chip pocket 11 and a second chip pocket 12 are formed in front of the first and second chip seats 8 and 9 in the rotation direction (see FIGS. 2 and 3).

A throw-away tip 10 having a substantially rectangular plate shape.
Is, for example, a negative tip having a cutting edge angle of about 90 degrees (a positive tip having a sharp cutting edge angle may be used), and each long side of the substantially rectangular upper and lower surfaces forming a parallel plane is the main cutting edge 14, and The four ridges in the plate thickness direction between the lower surfaces are the front cutting edges 15. When such a throw-away tip 10 is mounted on the front milling cutter 6, one tip 10 shown by a broken line in FIG. 1 is inclined at a predetermined angle α (for example, 15 °) with respect to the axis O of the cutter body 7, and 1 chip seat 8
Is mounted with the lower (upper) surface as the seating surface and the upper (lower) surface facing the outer periphery.
A. In the mounted state, the first throw-away tip 10A has a long side main cutting edge 14A on the outer peripheral side having a corner angle of an angle α, and a side surface 10a of the long side main cutting edge 14A is a rake face, 10b is used as a flank (see FIG. 2). Further, the cutting edge 15A forming the ridge in the plate thickness direction is a front cutting edge (see FIG. 1).

Further, another one chip 1 shown by a solid line in FIG.
0 is inclined at a predetermined angle β (for example, 45 °; β> α) with respect to the axis O of the cutter body 7, and the lower (upper) surface of the second tip seat 9 is the seating surface and the upper (lower) surface is the outer circumference. The second throw-away tip 10B is mounted on the second throw-away tip 10B. In the second throw-away tip 10B, in the mounted state, the long side main cutting edge 14B on the outer peripheral side has a corner angle of angle β, and the side surface 10a of the long side main cutting edge 14B is a rake face, 10b is a flank (see FIG. 3).
Further, the cutting edge 15B forming the ridge in the plate thickness direction is a front cutting edge (see FIG. 1). In this embodiment, the first and second throw-away tips 10A and 10B are used as vertical blades.

Then, the first throw-away tip 10A
And the second throw-away tip 10B are the cutter body 7
The main cutting edges 14A and 14B on the outer peripheral side having different corner angles intersect in the cutting region of the work material (referred to as the intersection point p) when viewed in the rotation direction of the corners of the main cutting edges 14A and 14B. The angles are in the relation of β> α, and the cutter height (distance from the base end of the cutter body 7 to the front cutting edge 15A, 15B tip) is the second throwaway tip 10A with the second throw. The relationship is larger than the away chip 10B. Therefore, the front cutting edge 15B of the second throw-away tip 10B does not participate in the cutting. Moreover, if the blade lengths from the front cutting edges 15A, 15B of the main cutting edges 14A, 14B to the intersection p are a and b, respectively, a <b is set. As a result, when the first or second throw-away tip 10A, 10B is used and then used as the second or first throw-away tip 10B, 10A,
The unused areas of the outer peripheral cutting edges 14A and 14B that have already been used can be newly used as the outer peripheral cutting edges 14B and 14A. The distance from the front cutting edge 15A of the first throw-away tip to the intersection p depends on the cutting depth of the work material and the two main cutting edges 14A and 14B before and after the intersection p perform cutting at the same time. It is set to an appropriate value so that it is set to, for example, 0.5 mm or more (2 mm in the embodiment).

In the cutter body 7 of the face mill 6 according to this embodiment, the first and second tip seats 8 on the outer periphery of the tip end of the cutter body 7,
According to 9, first and second throw-away tip 10
A and 10B are arranged alternately and in the same number at a predetermined interval. Moreover, the first and second throw-away tip 10
The radial rake angles of A and 10B are set to negative, and the axial rake angle is the first throwaway tip 1.
0A is set to negative, and the second throw-away tip 10B can be set to positive because the front cutting edge 15B does not participate in cutting (however, it may be negative). Therefore, for the main cutting edge 14 of the throw-away tip 10, it is possible to select a blade shape with good sharpness (particularly in the cutting edge region on the base end side from the intersection p).

Since this embodiment is constructed as described above, the front milling cutter 6 in which the first throw-away tip 10A and the second throw-away tip 10B are alternately arranged on the outer periphery of the tip of the cutter body 7 is used. When the work material W is cut, in the first throw-away tip 10A, from the tip of the main cutting edge 14A by the corner portion of the front side cutting edge 15A on the tip side by the ridge in the plate thickness direction and the long side on the outer peripheral side. Intersection p
Cutting is performed in the area up to (blade length a). Also, the second
In the throw-away tip 10B, the main cutting edge 14 on the outer peripheral side
Cutting is performed in the region from the intersection p of B to the base end side. Therefore, the processed side surface of the work material W is cut as a two-step inclined surface.

When cutting with the front milling cutter 6 according to this embodiment, the first throw-away tip 10A can be used because the area of the blade length a of the main cutting edge 14A or the front cutting edge 15A is broken or worn. Even if it disappears, the first
The same main cutting edge 14 is reattached from the tip seat 8 to the second tip seat 9 and used as the second throw-away tip 10B.
The unused area on the base end side from the intersection p of B can be used for cutting, and the same corner can be used twice for cutting. On the contrary, in the second throw-away tip 10B,
Even if the main cutting edge 14B becomes unusable due to chipping or wear, it is reattached to the first tip seat 8 and the same main cutting edge 14A (unused blade length as the first throw-away tip 10A is used). Area of flute length a (in b) and front cutting edge 1
5A can be used. Therefore, the throw-away tip 10 can use twice the four corners (two corners on one side in the case of a positive tip) of the upper and lower sides in the case of the negative tip, and the throw-away tip similar to the conventional one. By using, the number of usable corners is substantially doubled, and the service life can be significantly improved. Moreover, the second throw-away tip 1
Since the 0B main cutting edge 14B has a positive axial rake angle, sharpness is improved and cutting resistance can be reduced.

As described above, the face mill 6 of this embodiment
According to this, by using the throw-away tip 10 having the same shape as the conventional one, the number of usable corners can be substantially doubled and the tip life can be improved. Further, by alternately disposing both chips 10A and 10B, the cutting performance becomes stable. Moreover, in the cutting region of the main cutting edge 14B of the second throw-away tip 10B, there are advantages that the sharpness is particularly good and the cutting resistance is small.

In the above embodiment, the first tip seat 8 and the second tip seat 9 are alternately formed, and the first and second throw-away tips 10A and 10B are alternately mounted. Alternatively, it is possible to arrange the chips 10A and 10B in different numbers (together with the chip seats 8 and 9) and arrange them in a constant ratio arrangement. In this case, the stability of the cutting performance is maintained. Be drunk The first and second throw-away tips 10A, 10B are arranged in the same number or different numbers (the first tip seat 8 and the second tip seat 9 are also the same), and are arranged in an arbitrary order in the rotation direction of the cutter body 7. You may do it. Further, in the above-described embodiment, the throw-away tips 10A and 10B are mounted as vertical blades, but the present invention is not limited to this and may be mounted in other states in which the upper and lower surfaces of the tips are oriented in the rotational direction. Good. In short, it suffices that one throw-away tip 10 can be used by setting different cutting edge corner angles as the first and second throw-away tips 10A and 10B, thereby improving the life of the tip by substantially doubling the number of usable corners. And sharpness can be improved.

In each of the above-mentioned embodiments, the throwaway tip 10 has a substantially rectangular plate shape, but other appropriate polygonal plate shapes such as a substantially square plate shape and a triangular plate shape may be used. Good. Further, although the face mill 6 is used as the rolling tool for mounting the throw-away tip 10, it goes without saying that other milling cutters, end mills, or the like may be used.

[0020]

As described above, in the indexable milling tool according to the present invention, a plurality of indexable inserts are
The outer peripheral cutting edges of the first throw-away tip and the second throw-away tip, which are arranged as a first throw-away tip and a second throw-away tip having different cutting edge corner angles, respectively, and when viewed in the rotation direction of the cutter body. Since they intersect each other in the cutting area, the number of usable corners can be substantially doubled by using the throw-away tip having the same shape as the conventional one, and the tip life is improved. be able to.
Further, since the first throw-away tips and the second throw-away tips are arranged alternately and in the same number in the rotational direction of the cutter body, the cutting performance by both tips is stable. The throw-away tip is a negative type tip with a cutting edge angle of about 90 degrees, and one of the first and second throw-away tips with the larger cutting edge corner angle is installed so that the axial rake angle is positive. Therefore, the number of corners used is substantially doubled compared to the positive type insert, and the throw-away insert with the larger cutting edge corner angle can set the axial rake angle to positive, It has the advantages of particularly good sharpness and low cutting resistance. In addition, the tip length from the intersection of the outer cutting edges of the first and second throwaway tips is set longer for the tip with the larger tip corner angle. When used, the cutting blade of the unused portion at the time of previous use can be used as a new used portion of each outer peripheral cutting blade.

[Brief description of drawings]

FIG. 1 is a partial vertical cross-sectional view of a front milling cutter according to an embodiment of the present invention.

FIG. 2 is a side view showing a first throw-away tip portion of the front milling cutter shown in FIG.

3 is a side view showing a second throw-away tip portion of the front milling cutter shown in FIG. 1. FIG.

FIG. 4 is a partial cross-sectional view showing a state in which a throw-away tip of a conventional face milling cutter is mounted.

[Explanation of symbols]

 6 Front milling cutter 8 First tip seat 9 Second tip seat 10 Throw-away tip 10A First throw-away tip 10B Second throw-away tip 14A, 14B Main cutting edge 15A, 15B Front cutting edge

Claims (6)

[Claims] 1. A throw-away type cutting tool in which a plurality of throw-away tips each having a cutting edge are mounted on the outer peripheral portion of the tip of a cutter body, wherein the plurality of throw-away tips have cutting edge corner angles. Are arranged as a first throw-away tip and a second throw-away tip that are different from each other, and when viewed in the rotation direction of the cutter body, the outer cutting edges of the first throw-away tip and the second throw-away tip are in the cutting area. A rolling tool characterized by intersecting each other. 2. The cutting tool according to claim 1, wherein the first throw-away inserts and the second throw-away inserts are arranged alternately and in the same number in the rotational direction of the cutter body. 3. The throw-away tip is a negative type tip having a blade edge angle of about 90 degrees, and the one having a larger cutting edge corner angle among the first and second throw-away tips has a positive axial rake angle. The cutting tool according to claim 1 or 2, wherein the rolling tool is installed so as to be. 4. The tip having the larger cutting edge corner angle of the first and second throw-away tips has a front cutting edge located closer to the base end side than the front cutting edge of the other tip. The rolling tool according to any one of claims 1 to 3. 5. A tip having a larger tip corner angle is set to have a longer blade length on the tip side from the intersection of the outer peripheral cutting edges of the first and second throw-away tips. The rolling tool according to any one of claims 1 to 4. 6. The rolling tool according to claim 1, wherein the rolling tool is a face milling cutter, and the throw-away tip has a substantially rectangular plate shape.