JP2584176Y2 - 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 suitable for a cutting tool such as a face mill.

[0002]

2. Description of the Related Art Conventionally, as an example of this kind of cutting tool,
There is a face mill as shown in FIG. In this front milling cutter, grooves 2 for mounting a throw-away tip are provided on the outer peripheral side of the distal end of the tool body 1 in a circumferential direction. In each groove 2, a mounting surface 2a facing forward in the rotation direction of the tool body 1 is formed, and a seating surface of the throw-away tip 3 is seated and positioned on the mounting surface 2a, and a wedge member (not shown) Or by screwing a screw into a screw hole drilled in the tip 3
Will be fixed.

The indexable insert 3 has a rectangular plate shape as shown in FIGS. 5A and 5B, for example.
A surface opposed to the seating surface 3a seated on the mounting surface 2a of the tool body 1 is defined as an upper surface 3b, and a flat surface inclined outward from the seating surface 3a toward the upper surface 3b on four sides between the seating surface 3a and the upper surface 3b. Side surfaces 3c are respectively formed. And
A ridge line forming each side of the upper surface 3b constitutes a main cutting edge 4, a corner portion between the adjacent main cutting edges 4 is cut out to form a sub cutting edge 5, and constitutes a finishing blade. A rectangular corner surface 6 is provided by being cut out from the sub cutting edge 5b of 3b to the seating surface 3a. As shown in FIG. 6, the corners where the sub cutting edge 5 intersects with the main cutting edge 4 are chamfered 7 (constituting the cutting edge), and the chamfered portion 7 extends from the upper surface 3b to the seating surface 3a. The rectangular chamfered surface 8 is formed to extend. With such a throw-away tip 3 attached to the tool body 1 shown in FIG. 4, the sub-cutting edge 5 protrudes toward the tip end of the tool body 1, and the main cutting edge 4 adjacent thereto is inclined outward. Will be located.

[0004]

However, when the work material is cut sideways by the milling machine having such a configuration, for example, as shown in FIG. 6, a corner portion forming an intersection between the sub cutting edge 5 and the chamfer 7 is formed. a and the corner b that forms the boundary between the chamfer 7 and the main cutting edge 4 are liable to be chipped, which adversely affects the processing accuracy of the work material. Further, since the corners a and b are apt to be broken, frequent corner changes are required during cutting, so that the attaching / detaching operation is complicated, and the lifetime of the indexable tip 3 is short.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a throw-away insert in which a cutting edge at a corner portion and an intersection thereof are hardly damaged.

[0006]

In the indexable insert according to the present invention, the ridges forming each side of the surface facing the seating surface are the main cutting edges, and the ridge at the corner between the adjacent main cutting edges is the sub cutting edge. In the throw-away insert formed as a blade, a corner portion of a surface facing the seating surface forms an arc-shaped ridge line, and a central portion thereof is cut linearly to form a sub-cutting edge, and the sub-cutting edge and the main cutting edge are formed. And the arcuate ridge line between them is an arcuate cutting edge.

Further, the corner portion has a curved side surface with an arc-shaped cross section, and is cut in a substantially triangular shape from the auxiliary cutting edge toward the seating surface. Further, the honing is provided on the sub-cutting edge and the arcuate cutting edges on both sides of the sub-cutting edge on the surface facing the seating surface.

[0008]

Therefore, at the corner of the indexable insert, the connection from the main cutting edge to the arc-shaped cutting edge is smooth, and the connection from the arc-shaped cutting edge to the sub-cutting edge forms a large obtuse angle. Are connected to each other, so that the corners are hardly formed and are hardly broken. Moreover, the connecting portion between the arcuate cutting edge and the main cutting edge has a curved side surface, so that the strength is higher than that of the prismatic side surface. Honing also increases the strength of the cutting edge.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention will be described below with reference to FIGS. 1 to 3. The same reference numerals are used for the same parts or members as in the above-mentioned prior art, and the description is omitted. FIG.
(A) is a plan view of the throw away tip according to the embodiment,
2 (B) is a side view, FIG. 2 is an enlarged plan view of a corner portion of FIG. 1, and FIG. 3 is a sectional view taken along line XX of FIG. In the throw-away tip 10 shown in FIGS.
Each corner portion between the adjacent main cutting edges 4 on b is formed as an arc-shaped ridge line, and the central portion thereof is cut straight to form the sub cutting edge 11. And this secondary cutting edge 1
Each arc-shaped ridgeline connected to the main cutting edges 4 on both sides of the one constitutes arc-shaped cutting edges 12, 12, respectively.

The side surface of the corner portion of the throw-away insert 10 is formed as a curved side surface 13 having an arc-shaped cross section extending from an arc-shaped ridge line including the arc-shaped cutting blades 12 on the upper surface 3b to a seating surface 3a. And its upper surface 3b
The closer central portion is cut by a substantially triangular planar cut surface 14 extending from the sub cutting edge 11 to a position halfway in the seating surface 3a of the curved side surface 13 (see FIGS. 1B and 2). Also, the arc-shaped cutting edges 12, 1 at each corner of the upper surface 3b.
2 and the area of the secondary cutting edge 11 therebetween are honed, so that the arcuate cutting edges 12, 12 and the secondary cutting edge 11
Is the honing slope 15 of the upper surface 3b (see FIG. 3)
Is formed at the ridge line where the curved side surface 13 and the cut surface 14 intersect.

The throwaway tip 10 according to the present embodiment
Is constructed as described above, so that it is mounted on the tool body 1 of a face milling machine as shown in FIG. 4, for example, to perform cutting. Indexable tip 1 according to the present embodiment
0 indicates that the cutting edge is smoothly connected from a straight line to an arcuate curve from the main cutting edge 4 to the arcuate cutting edge 12 at each corner, and then forms a large obtuse angle from the arcuate cutting edge 12 to the sub cutting edge 11. At the same time, since one of the cutting edges 12 has an arc shape, it is smoothly carried over from the arc-shaped curve to a straight line, and a corner which is liable to be broken is hardly formed. Moreover, the cut surface 1
Since the intersection ridge line between the curved surface 4 and the curved side surface 13 is located in a direction gradually approaching a substantially triangular shape from the upper surface 3b toward the seating surface 3a, the auxiliary cutting edge 11 and the two arc-shaped cutting edges 12 are provided. In each of the connecting portions, the region of the curved side surface 13 which is thicker than the prism portion is located in the side surface direction, and the strength is increased. In addition, the auxiliary cutting edge 11 at the corner and the arcuate cutting edges 12 connected to both sides thereof are honed.
The strength of the cutting edges 1 and 12 is enhanced, so that the minor cutting edge portion is less likely to be lost.

As described above, according to this embodiment, the corner portion is hardly formed at the connecting portion between the sub-cutting edge 11 at the corner portion and the arc-shaped cutting blades 12 on both sides thereof.
Curved side surface 1 having a thicker side surface at the connecting portion between the blade and arcuate cutting edge 12
3, the strength of the sub-cutting edge 11 portion is extremely high, and it is unlikely to cause chipping. Therefore, there is an advantage that the lifetime of the throw-away tip 10 can be extended. In addition, the auxiliary cutting edge 11 and the arcuate cutting edge 12,
By providing the honing to 12, the cutting edge strength is further increased.

Here, an example of the shape and dimensions of the throw-away tip 10 according to the present embodiment is as follows, but it goes without saying that other dimensions and shapes can be set without being limited thereto. . Indexable Tip 1
0 is a substantially square plate, and one side of the upper surface 3b is about 12.7.
In the case of 0 mm, the width of the sub-cutting edge 11 in plan view is about 1.6 mm, the inclination angle of the cut surface 14 with respect to the vertical direction in side view is about 25 degrees, and the inclination angle of the curved side surface 13 with respect to the vertical direction is about 20 degrees. , A pair of arcuate cutting blades 12, 1
2 is about 2.4 mm, the width of the inclined surface of the honing in plan view is about 0.18 mm, and the upper surface 3
The inclination angle with respect to b was about 25 degrees.

In the above numerical example, the length (chord) of the sub-cutting edge 11 is set to 1.6 mm with respect to the radius of the arc-shaped ridge line of the corner portion of 2.4 mm. Needless to say, it can be set to the size of. Further, the shape of the throw-away tip 10 may be not only a rectangle as in the embodiment but also a triangle or a polygon. In the above-described embodiment, the throw-away insert for mounting the face mill has been described. However, the present invention is not limited to this embodiment, and the indexable insert according to the present invention can be mounted on another appropriate cutting tool.

[0015]

As described above, in the indexable insert according to the present invention, the corner portion forms an arc-shaped ridge line, and the center portion is cut linearly to form a sub cutting edge. Since the arc-shaped ridgeline between the cutting edge and the cutting edge is an arc-shaped cutting edge, almost no corner is formed at the connection between the sub-cutting edge and the arc-shaped cutting edge on both sides thereof, and the strength of the sub-cutting edge portion is extremely high. ,
Less likely to cause loss. Therefore, there is an advantage that the lifetime of the throw-away tip can be extended. Also, since the side surface of the corner portion has a curved side surface with an arc-shaped cross section and is cut into a substantially triangular shape from the sub cutting edge toward the seating surface direction,
Since the side surface of the connecting portion between the sub cutting edge and the arcuate cutting edge is formed by a thicker curved surface, the cutting edge strength is further increased. Moreover, by providing honing on these sub-cutting edges and arcuate cutting edges, the cutting edge strength is further increased.

[Brief description of the drawings]

1A is a plan view of a throw-away tip according to an embodiment of the present invention, and FIG. 1B is a side view of the same.

FIG. 2 is an enlarged plan view of a corner portion of FIG.

FIG. 3 is a sectional view taken along line XX of FIG. 2;

FIG. 4 is a cross-sectional view of a tool main body showing a general state in which a throw-away tip is mounted on a front milling machine.

FIG. 5A is a plan view of a conventional indexable insert, and FIG. 5B is a side view of the same.

FIG. 6 is an enlarged plan view of a corner portion of FIG.

[Explanation of symbols]

 Reference Signs List 4 main cutting edge 3a seating surface 10 indexable insert 11 sub cutting edge 12 arcuate cutting edge 13 curved side surface 14 cut surface

Claims (3)

(57) [Scope of request for utility model registration] 1. A throw-away insert in which a ridge forming each side of a surface facing a seating surface is a main cutting edge, and a ridge at a corner between adjacent main cutting edges is a sub-cutting edge. The corner portion of the surface facing the surface forms an arc-shaped ridge line, and the center portion is cut straight to be a secondary cutting edge,
A throw-away insert, wherein the arc-shaped ridge between the sub-cutting edge and the main cutting edge is an arc-shaped cutting edge. 2. The method according to claim 1, wherein the side surface of the corner portion has a curved side surface with an arc-shaped cross section, and is cut in a substantially triangular shape from the auxiliary cutting edge toward the seating surface. Indexable tip. 3. The indexable insert according to claim 1, wherein a honing is provided on the sub-cutting edge and the arcuate cutting edges on both sides of the sub-cutting edge on the surface facing the seating surface.