JPH10138031A - Milling tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent small cutting edges between nicks from being damaged and chatter or the like from being caused by partially overlapping nicks of adjacent cutting edges among plural cutting edges on which nicks are arranged in a milling tool, and arranging wide nicks on the other cutting edges. SOLUTION: An end mill 10 has four strips of cutting edges 11, and in the respective cutting edges 11, nicks 12 are respectively arranged in a plurality through a necessary interval. In this case, positions of the nicks 12 in the first and the third cutting edges 11 are made to coincide with each other, and positiones of the nicks 12 in the second and the fourth cutting edges 11 are made to coincide with each other. In the adjacent cutting edges 11, the nicks 12 are made to respectively exist over a wider range than small cutting edges 11a on the other cutting edges 11 in positions corresponding to the small cutting edges 11a between the nicks 12 in one cutting edges 11, and the nicks 12 in the respective cutting edges 11 are overlapped with each other in a necessary width (d). Therefore, damage of the small cutting edges 11a is restrained, and the occurrence of chatter or the like is restrained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rolling tool, such as an end mill, a taper reamer, or a drill, for rotating an object to be cut by a plurality of cutting blades. The present invention also relates to a rolling tool capable of performing stable cutting without causing variation in cutting resistance applied to each cutting edge even when provided.

[0002]

2. Description of the Related Art Conventionally, end mills, taper reamers,
A cutting tool such as a drill is rotated, and a workpiece is cut by a plurality of cutting blades provided on the cutting tool.In order to reduce cutting resistance applied to the cutting tool, JP-A-49-135283, JP-A-59-47110, and Japanese Utility Model Laid-Open No. 6-74219 propose that a plurality of notches called nicks are provided on each cutting edge at required intervals. ing.

[0003] In providing a plurality of nicks at required intervals on each cutting edge of a milling tool as described above,
Conventionally, when the workpiece is cut by each cutting edge in the milling tool, in order to prevent the uncut portion from being left on the workpiece, the nick portion is not overlapped on all the cutting edges. At the position corresponding to the nick portion of one cutting blade, the blade portion of the other cutting blade always exists.

[0004] Here, in an end mill 10 provided with four spiral cutting edges 11 as shown in FIG.
In providing the nicks 12 on each of the cutting edges 11, for example, as shown in FIG.
Nick 12 and second and fourth cutting edges 11
The position of the nick 12 is the same, and the portion of the other cutting edge 11 corresponding to the nick 12 of the one cutting edge 11 in the adjacent cutting edges 11 has a small cutting edge in a wider range than the nick 12. 11a is present, and
In each of the fourth cutting blades 11, the portion where the nick 12 does not exist is overlapped with the required width x.

When the nicks 12 are provided on the respective cutting blades 11 as described above, in the portion A shown in FIG. 2 where the nicks 12 are present, as shown in FIG. While only the second and fourth two cutting edges 11 are present, in the portion B where each cutting edge 11 overlaps with the required width x without the nick 12, as shown in FIG. , The first to fourth four cutting edges 11 were present.

When the above-described end mill 10 is rotated to cut an object to be cut by each of the cutting edges 11, the nick 12 is provided at the portion A where the nick 12 exists. The object to be cut is not cut by the two cutting edges 11, and the object to be cut is cut by the other two cutting edges 11, while the cutting thickness of one cutting edge 11 is equivalent to two cutting edges, In the part B where the respective cutting edges 11 overlap with the required width x without the nicks 12, the object to be cut is cut by the four cutting edges 11, and the cut thickness of one cutting edge 11 is as described above. It became half of the part of A.

For this reason, in one small cutting edge 11a between the nicks 12, there is a portion where the cutting thickness is equivalent to two blades and a portion where the cutting thickness is half and one cutting edge is generated. The cutting forces were partially different.

If the cutting resistance of one small cutting edge 11a between the nicks 12 is partially different as described above, the small cutting edge 11a is liable to be damaged, and chattering or the like occurs during cutting. The noise increases,
There have been problems such as fatigue fracture easily occurring in the tool.

In a tapered reamer 20 provided with two straight cutting edges 21 on the outer periphery as shown in FIG. 5, a nick 22 is generally provided for each of the cutting edges 21 in FIG. As shown in the drawing, a small cutting edge 21a is present in a range wider than the nick 22 in a portion of the other cutting edge 21 corresponding to a portion of the nick 22 in one cutting edge 21. The nonexistent portions are overlapped with the required width x.
In the drill 30 provided with two cutting edges 32 at the tip as shown in FIGS. 1A and 1B, when the nick 22 is provided on each cutting edge 31 at the tip, as shown in FIG. When the drill 30 is rotated, a small cutting edge 31 is provided in a range wider than the nick 32 on a portion of the other cutting edge 31 corresponding to the portion of the nick 32 of the one cutting edge 31.
a at each cutting edge 31
Are overlapped with the required width x.

Therefore, the taper reamer 20 as described above is used.
Also in the drill 30, as in the case of the end mill 10 described above, the small cutting edges 21 a,
31a, a portion having a different cutting force is generated, and the small cutting blade 2
There have been problems such as the breakage of 1a and 31a, the occurrence of chatter and the like at the time of cutting, the increase of cutting noise, and the possibility of fatigue fracture of the tool.

[0011]

SUMMARY OF THE INVENTION The present invention relates to a rolling tool, such as an end mill, a taper reamer, or a drill, for rotating an object to be cut with a plurality of cutting blades, wherein each cutting blade has a nick. It is an object to solve such a problem as described above.

That is, in the present invention, a nick is provided for each cutting blade in a cutting tool such as an end mill, a taper reamer, and a drill as described above, and the cutting tool is rotated to cut a workpiece by each cutting blade. If you choose to
There is no part where the cutting resistance differs between small nicks between nicks, and this small cutting blade is damaged during cutting, chattering occurs, cutting noise increases, and tool fatigue fracture is likely to occur It is an object of the present invention to make it possible to perform stable cutting without causing a problem.

[0013]

According to the present invention, there is provided a cutting tool having a plurality of cutting edges provided with nicks.
Nicks provided on adjacent cutting blades partially overlap,
A nick wider than the above-mentioned small cutting edge exists on the other cutting edge at a position corresponding to the small cutting edge between the nicks on one cutting edge.

In the case where the cutting tool according to the present invention is rotated to cut an object to be cut by each of the nick-provided cutting blades, one of the adjacent cutting blades is used. Since the small cutting edge between the nicks is located within the range of the nick of the other cutting edge, the cutting thickness of one small cutting edge between the nicks is constant, and the cutting thickness of one small cutting edge is reduced as in the related art. It does not change partly, resulting in different cutting forces,
In addition to suppressing the breakage of the small cutting edge, the occurrence of chatter and the like during cutting is also suppressed, so that cutting can be performed stably without increasing cutting noise or easily causing fatigue fracture in the tool. become.

Here, like the rolling tool in the present invention, the nicks provided on the adjacent cutting edges are made to partially overlap, and the small cutting edge between the nicks on one cutting edge is replaced by the other cutting edge. If it is located within the range of the nick in the above, there is a risk that the remaining nicks of these cutting edges may overlap during cutting, but such nicks may be caused by the collision of chips during cutting. It is removed from the workpiece.

Here, in order to ensure that the uncut portion generated at the time of cutting is removed from the object to be cut by collision of cut chips or the like, nicks overlap at adjacent cutting blades. It is preferable that the width of the part that is left is less than or equal to 0.2 mm and the width of the part that is left uncut is less than or equal to 0.2 mm.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a rolling tool according to the present invention will be specifically described below with reference to the accompanying drawings.

(Embodiment 1) In this embodiment,
The case where the milling tool is the end mill 10 as shown in FIG. 1 will be described.

Here, also in the end mill 10 in this embodiment, four spiral cutting blades 11 are provided, and a plurality of nicks 12 are provided on the respective cutting blades 11 at required intervals. ing.

Here, in the end mill 10 in this embodiment, the nick 12 is attached to each cutting edge 11 as described above.
In providing, as shown in FIG.
The positions of the nicks 12 on the second cutting edge 11 are the same, and the positions of the nicks 12 on the second and fourth cutting edges 11 are the same.

In addition, the first, second, and second adjacent
3rd and 3rd, 3rd and 4th, 4th and 1st
For each of the cutting edges 11, one of the cutting edges 11
In the other cutting edge 11 at a position corresponding to the small cutting edge 11a between the nicks 12, the nick 12 is present in a wider range than the small cutting edge 11a. To make them overlap.

When the nicks 12 are provided on the respective cutting blades 11 in this manner, the nicks 12 are not overlapped with each other as shown in FIG.
As shown in FIG. 3 above, only the first and third cutting edges 11 or the second and fourth cutting edges 11 are present, while the nick 12 has a required width. As shown in FIG. 8, none of the first to fourth cutting edges 11 is present in the portion B overlapping at d.

When the end mill 10 in this embodiment is rotated to cut the object to be cut by each cutting edge 11, the first and third portions A in the above-mentioned portion A where the nicks 12 do not overlap. Th cutting blade 11a
The object to be cut is sequentially cut by the second and fourth small cutting blades 11a, and the cut thickness of each small cutting blade 11a is reduced to two for all portions, and each small cutting blade 11a is cut. The cutting resistance is not partially different in the blade 11a, and the breakage of these small cutting blades 11a is suppressed, and the occurrence of chatter and the like at the time of cutting is also suppressed, so that the cutting noise increases, Fatigue failure is less likely to occur.

When an object to be cut is cut by the end mill 10, the nick 12 of each cutting edge 11 has no cutting edge 11 in a portion B where the nick 12 overlaps with a required width d. However, if the width d of the overlapping portion is set to 0.2 mm or less, the thickness of the uncut portion becomes thin, and the uncut portion is also removed from the workpiece by collision of chips generated at the time of cutting. become,
In particular, in the case of roughly cutting a workpiece, such uncut portions of the workpiece did not pose a problem.

The end mill 1 in this embodiment
At 0, the nicks 12 are provided up to the tip of the first and third cutting edges 11, but in order to enhance the cutting performance at the tip of the cutting edge 11, as shown in FIG. It is also possible not to provide the nick 12 at the tip.

In the case where the nick 12 is not provided at the tip of the cutting blade 11 as described above, the first to fourth fourth knives are provided at the tip of the cutting blade 11 as shown in FIG. There are two cutting edges 11, and the cutting thickness in this portion is one blade, and the cutting resistance is different from that of the portion where the nick 12 is provided. However, since the cutting resistance at the small cutting edge 11a between the nicks 12 is the same as described above, the occurrence of chatter and the like at the time of cutting is reduced as compared with the conventional one.

In the end mill 10 in the above embodiment, the nicks 12 are provided in parallel with the rotation direction of the cutting blades 11 when the nicks 12 are provided on the respective cutting blades 11, but as shown in FIG. Nick 12 has each cutting edge 11
In such a case, the boundary between the tip side of the nick 12 and the small cutting edge 11a acts as the auxiliary cutting edge 11b, and the nick 1
The uncut part at the portion where 2 overlaps is the auxiliary cutting edge 11
The cutting is performed to some extent by b, so that the uncut portion of the workpiece is reduced.

(Embodiment 2) In this embodiment,
A case where the milling tool is a taper reamer 20 provided with two straight cutting edges 21 on the outer periphery as shown in FIG. 11 will be described.

In the taper reamer 20 of this embodiment, as shown in FIG.
A nick 22 is provided on each cutting edge 21 of the strip at a required interval.

Here, in the taper reamer 20 of this embodiment, when the nick 22 is provided on each of the two straight cutting edges 21 as in the case of the end mill 10, one of the cutting edges 21 is provided. Nick 2 at 21
The nick 22 is attached to the other cutting edge 21 at a position corresponding to the small cutting edge 21a between the two in a wider range than the small cutting edge 21a.
And the nicks 22 of the respective cutting edges 21 overlap with the required width d.

The taper reamer 20 of this embodiment
Is rotated to cut the object to be cut by each of the above-described cutting edges 21, the portion corresponding to the small cutting edge 21 a between the nicks 22 in any one of the cutting edges 21 corresponds to this. The nicks 22 exist on the other cutting edge 21, and the cutting thickness of each small cutting edge 21a between the nicks 22 of each cutting edge 21 becomes two in every part, and the cutting resistance at these small cutting edges 21a. Are not partially different, the breakage of these small cutting edges 11a is suppressed, and the occurrence of chatter and the like during cutting is reduced, so that cutting noise increases and fatigue fracture occurs in the tool. It will be suppressed.

(Embodiment 3) In this embodiment,
A case where the milling tool is a drill 30 provided with two cutting blades 32 at the tip as shown in FIGS. 12A and 12B will be described.

In the drill 30 according to this embodiment, as shown in the figure, nicks 32 are provided at required intervals on two cutting blades 32 provided at the tips.

When the nick 32 is provided on each cutting edge 31 at the tip of the drill 30 in this manner, when the drill 30 is rotated, one of the cutting edges 3
The nicks 32 in each cutting edge 31 have a required width so that the nicks 32 in the other cutting edge 31 at a position corresponding to the small cutting edge 31a between the nicks 32 in 1 have a wider range than the small cutting edge 31a. d is set to overlap.

Then, even when the drill 30 of this embodiment is rotated to cut the workpiece by each cutting edge 31 at the tip thereof, the small nick 32 between any one of the cutting edges 31 is cut. In the portion where the cutting edge 31a exists, the nick 32 exists on the other corresponding cutting edge 31, and the cutting thickness of each small cutting edge 31a between the nicks 32 of each cutting edge 31 is 2 in all portions. The cutting forces at the small cutting edges 31a are not partially different from each other.
In addition to suppressing breakage of 1a, occurrence of chatter and the like during cutting is reduced, so that cutting noise is increased and fatigue fracture of the tool is suppressed.

[0036]

As described above in detail, in the rolling tool according to the present invention, the nicks provided on the adjacent cutting edges partially overlap and correspond to the small cutting edges between the nicks on one of the cutting edges. At the other cutting edge at the position, there is a nick wider than the above-mentioned small cutting edge, so if this rolling tool is rotated to cut the workpiece by each cutting edge, the In the matching cutting edge, since the small cutting edge between the nicks on one cutting edge is located within the range of the nick on the other cutting edge, the cutting thickness at one small cutting edge between the nicks is partially different. There is no longer any part with different resistance.

As a result, when the workpiece is cut by the milling tool of the present invention, the breakage of the small cutting edge is suppressed, and the occurrence of chatter and the like during cutting is suppressed, and the cutting noise is reduced. In this way, stable cutting can be performed without increasing the size of the tool or making the tool more susceptible to fatigue fracture.

Further, in the rolling tool according to the present invention, if the width of the portion where the nick overlaps on the adjacent cutting blades is set to 0.2 mm or less, the uncut portion remains at the portion where the nicks of these cutting blades overlap during cutting. Although there is a possibility that such a residue will be removed from the workpiece due to the collision of chips during the cutting, etc., such a residue will be removed, especially when roughing the workpiece. There was no problem with the remaining material.

[Brief description of the drawings]

FIG. 1 is a perspective view of a conventional end mill in which a nick is provided on each cutting blade.

FIG. 2 is a development view showing positions of nicks on each cutting edge of the conventional end mill shown in FIG.

FIG. 3 is an explanatory view showing a state of a portion A in each cutting blade of the end mill shown in FIG. 2;

FIG. 4 is an explanatory view showing a state of a portion B in each cutting edge of the end mill shown in FIG. 2;

FIG. 5 is an explanatory view of a tip portion of a conventional taper reamer provided with a nick on an outer peripheral cutting edge.

FIG. 6 is an explanatory view of a tip portion of a conventional drill provided with a nick at a tip cutting edge.

FIG. 7 is a developed view showing a state in which a nick is provided on each cutting edge in the end mill according to the first embodiment of the present invention.

8 is an explanatory diagram showing a state of a portion B in each cutting edge of the end mill shown in FIG. 7;

FIG. 9 is a developed view of a modified example in which the position where the nick is provided is changed in the end mill according to the first embodiment.

FIG. 10 is a developed view of a modified example in which the nick provided on each cutting blade is provided at right angles to the cutting blade in the end mill according to the first embodiment.

FIG. 11 is an explanatory diagram of a distal end portion of a taper reamer according to Embodiment 2 of the present invention.

FIG. 12 is an explanatory diagram of a tip portion of a drill according to Embodiment 3 of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 End mill 20 Taper reamer 30 Drill 11, 21, 31 Cutting edge 11a, 21a, 31a Small cutting edge 12, 22, 32 Nick d The width of the part where a nick overlaps

Claims (2)

[Claims] 1. In a rolling tool having a plurality of cutting edges provided with nicks, nicks provided on adjacent cutting edges partially overlap and correspond to small cutting edges between nicks on one of the cutting edges. A milling tool, characterized in that the other cutting edge at the position has a nick wider than the small cutting edge. 2. The milling tool according to claim 1, wherein
A milling tool characterized in that the width of a portion where nicks overlap between adjacent cutting blades is 0.2 mm or less.