JP3275695B2 - Indexable milling tools - 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 milling tool such as a throw-away ball end mill.

[0002]

2. Description of the Related Art Conventionally, as a throw-away type ball end mill, for example, there is one shown in FIGS. In this throw-away type ball end mill 1, concave grooves 3 and 4 having a substantially V-shaped cross section are substantially opposed to each other from a substantially hemispherical distal end toward a base end side of a substantially cylindrical tool body 2. , One of the grooves 3 has a tip reaching the rotation axis O at the tip of the tool body 2, and the other groove 4 has a tip having the rotation axis O
Starting from a position slightly away from the base end. The wall surface 3a of the concave groove 3 facing forward in the rotation direction of the tool body 2
, A plurality of throw-away tips 5 having, for example, a substantially triangular plate shape are attached at predetermined intervals from the distal end side to the proximal end side. A slight gap 8 is provided between the adjacent throw-away chips 5,5. Also, the cutting edge 6a is located on the wall surface 4a of the concave groove 4 (not shown in the figure) facing forward in the rotation direction of the tool body 2 at a position shifted from the cutting edge 5a of the throw-away tip 5 in the direction of the rotation axis O. So that the throw-away tip 6 has a similar shape from the distal end to the proximal end.
Are mounted at predetermined intervals, and a slight gap 8 is provided between the adjacent throw-away chips 6, 6.

[0003] These throw-away chips 5, 6
In the rotation locus, the adjacent cutting blades 5a and 6a are arranged so as to overlap each other. In addition, each groove 3, 4
Form chip pockets respectively. In the ball end mill 1 shown in FIGS. 8 and 9, each of the concave grooves 3 and 4 is formed so as to be inclined so as to form a predetermined angle with respect to the rotation axis O (see FIG. 8). Wall surface 3a,
The throw-away tips 5, 6 attached to the 4a are also seated stepwise at positions gradually delayed in the rotational direction from the distal end toward the proximal end.

[0004]

When cutting a workpiece with such a throw-away type ball end mill 1, the cutting edges 5a, 6 of the respective throw-away tips 5, 6 are cut.
The chips shaved in a run on the rake faces of the chips 5 and 6 and the wall faces 3 b and 4 which face rearward in the rotation direction of the grooves 3 and 4.
b, and curls in the air, and the chips 5, 5, 6, 6
As a result, the chips enter the gaps 8, 8, and the chips are caught and clogged in the gaps 8, so that there is no place for chips to escape. For this reason, the chips are clogged in the gap 8, and the chip discharge performance is deteriorated. The chips may interfere with the machined surface of the work material or the tool body 2 and may be rubbed, the chips 5 and 6 may be damaged, or There is a problem that chips are welded to the cutting edges 5a and 6a.

In view of the above problems, the present invention prevents chip clogging in the vicinity of a throw-away chip, improves chip discharge, and rubs a workpiece or tool with chips, chipping, etc. It is an object of the present invention to provide a throw-away type milling tool capable of preventing the occurrence of the above problem.

[0006]

SUMMARY OF THE INVENTION A throwaway milling tool according to the present invention is a throwaway milling tool having a cutting body having a cutting edge disposed on a tool body. A groove for chip discharge is formed adjacent to the side in a direction intersecting the rotation axis of the tool body , and this groove has an arc-shaped or V-shaped cross section, or
Is characterized in that it has any one of a U-shape . Chips generated by the cutting edge during cutting run along the chip rake face and curl, and flow near the base end of the throw-away insert, but flow smoothly in the groove and do not clog the chip. Also, do not scrape the work material or the tool body.

A throw-away milling tool according to the present invention is a throw-away milling tool having a plurality of throw-away inserts having cutting edges arranged on a tool body. A groove is formed between the two indexable inserts, and this groove has a cross section
Either arc, V-shape or U-shape
And extends in a direction intersecting the rotation axis. The chips flow into the gap between the throw-away chips, and travel smoothly in the groove to be discharged. The groove may be connected to a tip pocket on which the throw-away tip is mounted. In this case, the groove may be formed in a direction orthogonal to the rotation axis of the tool body. Alternatively, the groove may be formed in a substantially spiral shape so as to extend in a direction intersecting the rotation axis of the tool body and gradually approach the base end side. A groove may be formed in a direction intersecting the rotation axis, adjacent to the proximal end of the throwaway tip located closest to the proximal end.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. 1 to 4. The same reference numerals are used for the same parts or members as those in the above-mentioned prior art, and the description is given. Omitted. FIG. 1 is an external view of a throw-away type ball end mill showing a first embodiment of the present invention, FIG. 2 is an external view of a throw-away type ball end mill viewed from a different angle from FIG. 1, and FIG. 3 is a throw-away type ball end mill. FIG. 4 is a cross-sectional view taken along line AA of FIG. 3. FIG.
In the throw-away type ball end mill 10 shown in FIG.
And are formed so as to substantially face each other in a direction substantially parallel to. Then, with respect to the throw-away chips 5 arranged on the wall surface 16a facing forward in the rotation direction of the one concave groove 16 extending to the tip of the tool body 2, the proximal end side of each of the throw-away chips 5 on the outer peripheral surface of the tool body 2. Each of the grooves 12 is formed with a chip discharge groove 12 and extends in a direction substantially perpendicular to the rotation axis O.

These grooves 12 have, for example, an arc-shaped cross section, and are formed in a substantially arc shape so as to communicate from the wall surface 16a of the concave groove 16 to the other concave groove 18, and are substantially parallel to each other. The groove width of the groove 12 is equal to or larger than the interval of the gap 8 between each of the adjacent throw-away chips 5, 5, and in the example shown in FIGS. The groove width is set so as to slightly overlap the seating surface of the throw-away tip 5. Also, the other groove 1
Also in FIG. 8, a chip discharging groove 14 similar to the groove 12 is formed on the base end side of the throw-away tip 6, and extends to the concave groove 16. These grooves 14 are also formed parallel to each other in a direction substantially orthogonal to the rotation axis O.

Since the throw-away type ball end mill 10 according to the present embodiment has the above-described configuration, when cutting a work material with the ball end mill 10, the cutting edge of each of the throw-away tips 5, 6 is used. Chips cut at 5a and 6a run on the rake faces of the chips 5 and 6 and face the wall surfaces 16b and 1 facing rearward in the rotation direction of the grooves 16 and 18.
8b and is curled. And the cutting blade 5
a, 6a flows into a region such as the gap 8 adjacent to the base end side,
It is introduced into each of the grooves 12, 14 and travels in the grooves. Therefore, these chips smoothly flow in the grooves 12 and 14 without clogging the gap 8 between the chips, and
6 will be discharged.

As described above, according to the present embodiment, in a throw-away type ball end mill in which a plurality of throw-away chips 5 and 6 are arranged, generated chips are not clogged between adjacent chips. The chips 5 and 6 flow smoothly through the grooves 12 and 14 provided on the base end side thereof and are smoothly discharged. Therefore, the processing surface of the work material and the tool body 2 may be rubbed by chip clogging, and ,
6 can be effectively prevented from being lost. Similarly, the chips generated by the chips 5 and 6 on the most proximal side also have grooves 12 and
14 flows smoothly and is discharged.

FIG. 5 shows a modification of the above embodiment. In this modification, with respect to the tool body 2, the concave grooves 16, 18 are formed in the longitudinal direction at a slight angle with respect to the rotation axis O. For this reason, the plurality of indexable inserts 5 mounted on the wall surface 16a of the concave groove 16 that faces the rotation direction of the tool body 2 moves from the distal end toward the proximal end,
It is positioned so as to be gradually delayed in the rotation direction of the tool body 2. A concave groove 18 (not shown) formed at a position facing the concave groove 16 has substantially the same shape as the concave groove 16, and the plurality of throw-away tips 6 mounted on the wall surface 18a facing the rotation direction have a tip end. It is positioned so as to be gradually delayed in the rotation direction of the tool main body 2 from the side toward the base end side. With such a configuration, when the ball end mill 20 is rotated and cut, the timing at which each of the throw-away tips 5 and 6 abuts on the workpiece from the distal end toward the proximal end is gradually delayed. As in the embodiment, since the indexable inserts 5 and 6 do not hit the work material at once, the impact at the time of cutting can be reduced.

FIG. 6 shows a second embodiment of the present invention. In the throw-away type ball end mill 30 shown in the present embodiment, the groove 22 formed adjacent to the base end side of the throw-away tip 5 mounted on the wall surface 16a of the concave groove 16 is different from the concave groove 16 in the other concave side. It is inclined so as to gradually approach the base end side toward the groove 18. Similarly, groove 1
The groove 24 formed adjacent to the proximal end side of the throw-away tip 6 mounted on the wall surface 18a of the taper 8 is inclined so as to gradually approach the proximal end side from the concave groove 18 toward the other concave groove 16. The grooves 22 and 24 are formed spirally and continuously on the outer peripheral surface of the tool body 2 as shown in FIG. The throw-away chips 5, 6 may be arranged on the wall surfaces 16a, 18a between the 22, 22.

In the above-described embodiment, the groove 1 is located adjacent to the proximal end of the most proximal throw-away tips 5, 6.
2 and 14, the groove 1 on the most proximal side is provided.
The chips 2 and 14 do not have to be provided with a chip on the base end side, and thus need not be provided. In the above-described embodiment, the width of the chips 12, 14 and the like for discharging chips is the same as or larger than the width between the chips 5, 5, 6, 6 adjacent in the direction of the rotation axis O. The groove width may be smaller than the width between the chips, depending on the size of the width between the chips 5, 5, 6, and 6. In this case, it is preferable that the groove is formed adjacent to the tip-away tip. The cross section of each of the grooves 12, 14 and the like is not limited to an arc shape, but may be an appropriate shape such as a V-shape or a U-shape. In the above-described embodiment, the throw-away type ball end mill has been described. However, the present invention is not limited to this, and may be applied to various end mills such as a radius end mill and other multi-edge milling tools. Can be.

Further, in adopting the present invention, the adjacent throw-away chips do not necessarily need to be disposed with a gap therebetween in the direction of the rotation axis O, and may be disposed such that their rotation trajectories overlap each other. Further, regarding the arrangement of the indexable inserts, in the above-described embodiment, the two concave grooves 16,
Although 18 is formed as a chip pocket, the present invention is not limited to this, and only one groove may be formed as a chip pocket, or three or more grooves may be formed. In this case, if two or more indexable inserts are provided in one tip pocket in the direction of the rotation axis O, a chip discharge groove can be formed at the base end side of each tip. Further, even when only one chip is provided, by forming a groove on the base end side, chips can be discharged more smoothly, and abrasion of a work material or a tool body can be suppressed.

[0016]

As described above, in the throw-away type milling tool according to the present invention, a chip discharge groove is formed adjacent to the base end side of the throw-away insert in a direction intersecting the rotation axis of the tool body. This groove has an arc-shaped cross section or V
The shape is either U-shaped or U-shaped, so that the chips generated by the cutting edge of the insert can be discharged smoothly, and the work material and the tool body can be prevented from rubbing, resulting in chip breakage. The welding of chips can be prevented. Further, in the throw-away milling tool according to the present invention, a groove is formed between two indexable inserts adjacent to each other in the rotation axis direction, and the cross-section of the groove is arc-shaped, or V-shaped, or U-shaped
Since it has a misaligned shape and extends in the direction intersecting the axis of rotation, the generated chips can be smoothly discharged without clogging between adjacent chips, and as a result, By preventing abrasion, chip loss and chip welding can be prevented. Further, since the groove is connected to the chip pocket on which the throw-away chip is mounted, chips are smoothly discharged from the chip discharge groove via the chip pocket.

[Brief description of the drawings]

FIG. 1 is an external view of a throw-away type ball end mill according to a first embodiment of the present invention.

FIG. 2 is an external view of the ball end mill shown in FIG. 1 as viewed from a different angle.

FIG. 3 is an enlarged view of a main part of the ball end mill shown in FIGS. 1 and 2;

4 is a sectional view of the ball end mill shown in FIG. 3 taken along line AA.

FIG. 5 is an external view of a main part of a throw-away type ball end mill showing a modification of the first embodiment of the present invention.

FIG. 6 is an external view of a main part of a throw-away type ball end mill showing a second embodiment of the present invention.

FIG. 7 is a view showing a process of manufacturing the ball end mill shown in FIG. 6;

FIG. 8 is an external view of a conventional ball end mill.

FIG. 9 is an enlarged view of a main part of the ball end mill shown in FIG.

[Explanation of symbols]

 2 Tool body 5, 6 Throw-away insert 5a, 6a Cutting edge 10, 20, 30 Throw-away type ball end mill 12, 14, 22, 24 Groove 16, 18 Groove O Rotation axis

──────────────────────────────────────────────────続 き Continuing from the front page (56) References Japanese Utility Model Sho-62-50011 (JP, U) Seco Cutting Tool Catalog '93 -'94, Seco Tools Japan K.K., 290 (58) Fields surveyed ( Int.Cl. ⁷ , DB name) B23C 5/10

Claims (3)

(57) [Claims] 1. A throw-away type milling tool having a throw-away insert having a cutting edge disposed on a tool main body, wherein the throw-away milling tool intersects a rotation axis of the tool main body adjacent to a base end side of the throw-away insert. A chip discharge groove is formed in the direction, and this groove has an arc-shaped cross section or a V-shaped cross section.
A throw-away type milling tool characterized in that it has a shape or a U-shape . 2. A throw-away milling tool comprising a plurality of indexable inserts having cutting edges disposed on a tool body, wherein a groove is provided between two indexable inserts adjacent to each other in the direction of the axis of rotation of the tool body. This groove has an arc-shaped cross section, a V-shaped cross section, or a U-shaped cross section.
A throw-away type milling tool characterized in that it has a misaligned shape and extends in a direction intersecting the rotation axis. 3. The indexable cutting tool according to claim 1, wherein the groove is connected to a tip pocket in which the indexable tip is mounted.