JPS62292312A - End mill - Google Patents

Abstract

PURPOSE:To prevent an end mill from inclusion of chips without degrading the strength of cutting edge by forming the end face of an end mill body with a slant surface located on the axial endmost of cutting edge and inclined to a plane orthogonal to the axis of said body. CONSTITUTION:The side face W1 and bottom surface W2 of a workpiece W are respectively cut by cutting edges 14 of a throwaway tip 13 and bottom edges 15 of the throw-away tip 13 at the endmost portion of an end mill body 10. And since the end mill body 10 is formed on the end face 16 with a slant surface, a large gap 17 is formed between the end face 16 and the bottom surface W2 of the workpiece W. Thus, particularly in the throw-away tip 13 at the end side of end mill body 10 is prevented the occurrence of inclusion of ships so that chips cut by the throw-away tip 13 at the base end side of end mill body 10 are not rubbed between said tip and the bottom surface W2 of workpiece W even if they drop to the end 16 side. As a result, the cutting edges 14 and the body 10 itself are not damaged and the roughness of bottom surface W2 is never degraded.

Description

[Detailed Description of the Invention] 3. Detailed Description of the Invention [Field of Industrial Application] This invention involves cutting the outer periphery of a cylindrical end mill body that rotates around its axis from its tip to its base. This invention relates to an end mill with a blade formed therein.

[Prior Art] Generally, when performing groove processing or stepped processing on a workpiece, various end mills are used in which a cutting edge is formed along the axial direction on the outer periphery of the tool body.

9 and 10 show a conventional end mill of this type, which is a throw-away type end mill in which a plurality of indexable tips are detachably attached as the cutting blades, and the reference numeral 1 in the figures shows the end mill. This shows the main body.

This end mill body 1 has a generally cylindrical appearance with a shank portion 2 formed at its base end, and its distal end surface 3 is formed by a plane perpendicular to the axis.

A total of six tip pockets 4 are formed on the outer periphery of the end mill main body 1 at equal intervals in the circumferential direction and in positions that form a spiral as a whole from the distal end toward the proximal end. A groove-shaped chip mounting seat 5 is formed on the wall surface of each chip pocket 4 in the direction of rotation.

A throw-away tip 6 made of cemented carbide or the like is removably attached to each tip mounting seat 5 by a clamp 7. These throwaway tips 6...
・ is the cutting blade 8 that protrudes from the outer periphery of the end mill body l.
... are installed in succession in the axial direction in their respective rotational trajectories. Also, this end mill body 1
The indexable tip 6 located at the most distal end of the tip 6 is mounted with the cutting edge 9 adjacent to the cutting edge 8 thereof protruding toward the tip side of the end mill body l.

In the above conventional end mill having the above configuration,
End mill body! With the rotation of , the cutting blades 8 of the indexable tips 6 cut the side wall Wl of the workpiece W, and the cutting blades 9 of the indexable tip 6 at the tip cut the bottom surface W of the workpiece W. are cut to form grooves and stepped portions in this workpiece W.

[Problems to be Solved by the Invention]However, in the conventional end mill described above,
As shown in the figure, the end mill body l and the side wall W of the workpiece W
, and the bottom surface W are small, so that so-called chips are likely to get caught, and as a result, the cutting edge 9, which is the bottom edge, is likely to be damaged and the end mill body 1 is likely to be damaged. There was a drawback. Moreover, if the chips cut by the indexable tip 6 on the base end side of the end mill body l fall onto the bottom surface W of the workpiece W, the chips will fall onto the tip surface 3 when the end mill is fed laterally. It is rubbed between the bottom surface W of the workpiece W, and as a result, the bottom surface W,
There was also the problem of a decrease in surface roughness.

Conversely, if the overhang II (the amount of protrusion from the outer periphery of the end mill main body l) of the cutting edge 8 of the indexable insert 6 is increased in order to increase the gaps L+, I, and t, the strength of the cutting edge will decrease. There was a problem in that it could no longer withstand medium-sized cutting that is normally used.

[Purpose of the Invention] This invention was made in view of the above circumstances, and can prevent chips from getting stuck without reducing the strength of the cutting edge, thereby reducing chipping of the bottom edge and surface roughness of the workpiece. An object of the present invention is to provide an end mill that does not cause a decrease in sharpness or the like.

[Means for solving the problem] The end mill of the present invention has a tip surface of the end mill body that
The tip of the cutting blade of this end mill is the most extreme end in the axial direction, and is formed by an inclined surface that is inclined with respect to a plane perpendicular to the axis of the end mill body.

[Operation] In the end mill having the above configuration, a large gap is formed between the tip surface of the end mill body and the bottom surface of the workpiece.

As a result, so-called chip jamming does not occur, and the generated chips are not rubbed between the tip surface of the end mill body and the bottom surface of the workpiece.

(Example) FIGS. 1 and 2 show an example of an end mill according to the present invention, and reference numeral 10 in the figures indicates an end mill main body having a generally circular external appearance.

On the outer periphery of this end mill body IO, a pair of chip pockets 11, !, each extending tO in the axial direction are located at symmetrical positions with respect to the axis. Three chip mounting seats 12 are formed on the wall surface of each chip pocket II facing the rotational direction so as to be alternated in the axial direction. And these chip mounting seats 1
Each of the diamond-shaped indexable inserts 13... is removably attached to each of the inserts 2... with the respective cutting edges +4 continuous in the axial direction in the mutual rotation locus. The auxiliary cutting edge adjacent to the cutting edge L4 of the indexable tip 13 located at the most distal end of the end mill main body IO is the bottom edge 15.

The distal end surface 16 of the end mill main body IO has the most distal end where the indexable tip 13 is positioned as the distal end in the axial direction, and is inclined at a predetermined angle with respect to a plane orthogonal to the axis. It is formed by an inclined surface.

In the end mill of this example having the above configuration, the cutting edge I4 of the indexable tip 13... cuts the side surface Wl of the workpiece W, and the cutting edge I4 of the indexable tip 13... The bottom surface W of the work material W is cut using the bottom blade 15.

In such an end mill, the end mill body lO
Since the distal end surface 16 of the first
As shown in the figure, the tip surface 16 and the bottom surface W of the workpiece W,
A large gap 17 is formed between the two. Therefore, it is possible to reliably prevent so-called chips from being caught, especially in the indexable tip 13 located on the tip side of the end mill main body IO. Moreover, even if the chips cut by the indexable tip 13 located on the base end side of the end mill body 10 fall onto the distal end surface 16 side of the end mill body 10, the chips will fall on the bottom surface W of the workpiece W.
There will be no friction between the two.

As a result, the chip discharge performance is excellent, and furthermore, the chips do not cause damage to the cutting blades 14 of the indexable tips 13 located at the tip side of the end mill main body IO or the end mill main body 10 itself. There is also no fear that the surface roughness of the bottom surface W of the workpiece W will be reduced.

[Other Embodiments Figures 3 to 5 show a second embodiment of this invention.
In this end mill, two indexable tips 21a and 21b are mounted on the outer periphery of the tip of the end mill body 20 at symmetrical positions with respect to the axis. Further, on the outer periphery of the end mill body 20, two indexable tips 22 are arranged circumferentially from the pair of indexable tips 21a, 21b toward the proximal end of the end mill body 20. They are mounted at equal intervals in the direction.

The distal end portion 23 of the end mill body 20 includes an inclined surface 24 that slopes from one indexable tip 2Ia toward the proximal end of the end mill body 20, with the line connecting the indexable tips 21a and 21b as the boundary; It is formed by an inclined surface 25 which is inclined from the other indexable tip 21b toward the base end side of the end mill main body 20.

Further, FIGS. 6 to 8 show a third embodiment of the present invention, and in this end mill, an end mill main body 30
Six indexable tips 31 are attached to the outer periphery of the tip in a spiral pattern from the distal end to the proximal end.

The distal end surface 32 of this end mill main body 30 has indexable tips 3 arranged sequentially from the distal end toward the proximal end.
1... is formed by a spiral inclined surface that gradually slopes toward the proximal end of the end mill main body 30.

Even in the end mills described in these second and third embodiments, the tip surface 2 of each end mill main body 20.30 during cutting.
3. There is a large gap 26 between 32 and the bottom surface W of the workpiece W.
．． 33 is formed, so that the same effect as the end mill shown in the first embodiment can be obtained.

In the above embodiments, an indexable end mill is described in which indexable tips 13.21a12lb, 22.31 are attached as cutting blades to the outer periphery of the endmill main body 10.20.30. The present invention is not limited to this, and similar effects can be obtained even with a so-called solid type end mill in which a cutting blade is integrally formed on the outer periphery of the end mill body.

[Effects of the Invention] As explained above, the end mill of the present invention has a tip end face of the end mill body, and the tip of the cutting blade of this end mill is the most extreme part in the axial direction, and the end mill is perpendicular to the axis of the end mill body. Since it is formed by an inclined surface that is inclined with respect to the plane, a large gap is not formed between the tip of the end mill body and the bottom of the workpiece, which prevents the so-called chip jamming, resulting in improved cutting edge strength. It is possible to obtain excellent effects such as being able to prevent damage to the bottom edge and a decrease in the roughness of the workpiece without reducing the roughness.

[Brief explanation of drawings]

1 and 2 show a first embodiment of an end mill according to the present invention, FIG. 1 is a front view, FIG. 2 is a side view, and FIGS. 3 to 5 are a second embodiment of the present invention. 3 is a front view, FIG. 4 is a side view, FIG. 5 is a perspective view showing the general shape of the end face of the end mill body, and FIGS. 6 to 8 are third views of the present invention. This shows an example, and FIG. 6 is a front view;
Fig. 7 is a side view, Fig. 8 is a perspective view showing the general shape of the tip end face of the end mill body, Fig. 9 and Fig. 1O show a conventional end mill, Fig. 9 is a front view, and Fig. 1O is a front view. is a side view. 10.20.30...End mill body, +3
．． 21 a, 2 l b, 22.31 ・-= Throwaway tip, 14... Cutting blade, 15.
...Bottom blade, +6.23.32...Tip surface, 17.26.33...Gap, 24.25...Slanted surface, W... ... Work material, W, ... Work material side, W, ...
Bottom surface of work material.

Claims (1)

[Claims] In an end mill in which a cutting blade is formed on the outer periphery of a cylindrical end mill body from the tip end to the base end, the tip end of the cutting blade is located at the tip end of the end mill body in the axial direction. What is claimed is: 1. An end mill characterized in that the end mill is formed with an inclined surface that is inclined with respect to a plane perpendicular to the axis of the end mill body.