JP2002361514A - Rotary cutting tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce manhour, to shorten working time and to reduce cost by devising a rotary cutting tool to simultaneously finish a product shape only in one process even when a cutting surface is a curved surface, a complicated shaped surface, etc., at the time of finishing the product shape by a plurality of working such as intermediate finishing and final finishing. SOLUTION: A region θb on the upstream side of a cutting blade 3k of a first cutting blade group 3 is made wider than a region θa on the downstream side by arranging a plurality of the cutting blades 3k of the first cutting blade group 3 with equal intervals, arranging a plurality of cutting blades 4k of a second cutting blade group 4 with equal intervals and slipping phases of the first cutting blade group 3 and the second cutting blade group 4 from each other on a bottom part outer peripheral part of a tool main body 2. Additionally, the cutting blades 3k of the first cutting blade group 3 are made of a cemented carbide material, and the cutting blades 4k of the second cutting blade group 4 are made of a CBN material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary cutting tool which is suitable for, for example, finishing a rough-worked workpiece by finishing.

[0002]

2. Description of the Related Art Conventionally, for example, in order to finish a rough-processed work into a final product shape, it is common to go through each process such as a semi-finishing process and a final finishing process. Finishing using a finishing tool. On the other hand, in a milling cutter for plane cutting, a technique in which a plurality of cutting blades are provided on one tool to perform rough finishing, precision finishing, etc.
No.-95519 is known. In this technique, a plurality of disk substrates having steps and different diameters are formed on a milling substrate, and a cutting edge is implanted on a peripheral portion of each disk substrate. Thus, rough finishing, precision finishing, and the like are performed by the cutting blades of the disk base at each stage.

[0003]

However, as in the former case, the method of finishing a plurality of processes such as semi-finishing and final finishing with different tools is time-consuming and efficient. This was not a method, and there was a limit to cost reduction. In addition, the latter JP-A-56-955.
As in No. 19, a method of providing cutting blades on a plurality of disc substrates having different diameters having a step cannot perform rough finishing and precision finishing simultaneously in one process, and the cutting surface is curved or complicated. In the case of a shape surface, there is a problem that it cannot be applied.

[0004] Therefore, the present invention enables a plurality of processes such as semi-finishing and final finishing to be performed simultaneously in a single step even if the cutting surface is a curved surface or a complex-shaped surface, thereby reducing man-hours and processing. It is intended to reduce the time and cost.

[0005]

To achieve the above object, the present invention relates to a rotary cutting tool provided with a blade for contouring a workpiece in accordance with a product shape, wherein a plurality of cutting blades are used as the blade. Are arranged at equal intervals on the bottom outer peripheral portion of the tool body, and the number of cutting blades corresponding to the first cutting blade group are arranged at equal intervals on the bottom outer peripheral portion of the tool body. A second group of cutting blades is provided, and the first group of cutting blades and the second group of cutting blades are arranged so that the intervals between adjacent cutting blades are unequal.

[0006] While rotating such a rotary cutting tool, the contour is cut by processing and feeding, for example, in a direction perpendicular to the direction of the rotation axis. The cutting edge of the first cutting edge group adjacent to each other and the second cutting edge, By arranging the intervals of the cutting blades of the cutting blade group to be unequal, for example, in a place where the interval between the cutting blades is wide, the cutting amount of the cutting blade moving between them increases,
In a place where the interval between the cutting blades is small, the cutting amount of the cutting blade moving between the cutting edges is reduced, so that the cutting amount of the first cutting blade group and the cutting amount of the second cutting blade group can be changed. . For this reason, for example, a cutting blade group with a large amount of cutting is used as a semi-finishing cutting edge, and a cutting blade group with a small cutting amount is used as a final finishing cutting blade. You can do it.

Incidentally, it is not necessary to provide a difference between the cutting edge of the first cutting blade group and the tip of the second cutting blade group, and the like.
If the movement of such a tool is controlled by, for example, NC control or the like, a curved surface or a complex-shaped surface can be easily processed. The number of cutting blades in each cutting blade group is arbitrary.

In the present invention, the first cutting blade group and the second
In the arrangement of the cutting blade group, the interval from the cutting edge of the first cutting blade group to the cutting edge of the second cutting blade group is the second in the rotation direction.
The distance from the cutting edge of the first cutting edge group to the cutting edge of the first cutting edge group is set to be wider by a predetermined range. By appropriately adjusting the ratio of this range, the ratio of the cutting amount of the first cutting blade group to the cutting amount of the second cutting blade group can be appropriately set.

In the present invention, the cutting edge of the first cutting blade group is made of a carbide material, and the cutting edge of the second cutting blade group is made of a CBN (cubic boron nitride) material. Thus, the cutting edge of the first cutting blade group is made of a carbide material, and the cutting edge of the second cutting blade group is made of CB.
The use of N (cubic boron nitride) material is suitable for performing the semi-finishing with the first cutting blade group and performing the final finishing with the second cutting blade group.

In the present invention, the cutting blades of the second cutting blade group have a smaller thickness and a sharper rake angle than the cutting blades of the first cutting blade group. Thus, the cutting edge of the second cutting blade group for final finishing is thinner than the cutting edge of the first cutting blade group for semi-finishing,
It is more preferable that the rake angle is an acute angle.

[0011]

Embodiments of the present invention will be described with reference to the accompanying drawings. Here, FIG. 1 is a perspective view showing an example of a rotary cutting tool according to the present invention, and FIG. 2 is a front view of the tool.

[0012] The rotary cutting tool according to the present invention enables a rough-worked workpiece to be simultaneously processed in a single processing step when finishing a plurality of steps such as semi-finishing and final finishing. It aims to reduce man-hours, processing time, and cost.

That is, as shown in FIGS. 1 and 2, the rotary cutting tool 1 includes a tool body 2, a first group of cutting blades 3 disposed on an outer peripheral portion on the bottom side of the tool body 2, and The first cutting blade group 3 includes three cutting blades 3k at equal circumferential intervals, and the second cutting blade group 4 includes:
Three cutting blades 4k are provided at equal circumferential intervals.

The arrangement of the first cutting blade group 3 and the second cutting blade group 4 is such that the intervals between adjacent cutting blades are unequal. When attention is paid to any one of the cutting edges 3k, the interval θb between the adjacent cutting edge 4k on the rotation upstream side and the cutting edge 4k on the rotation downstream side
It is set to be wider than the interval θa with respect to k.

Here, the relationship between θa and θb is determined by the amount of cut per blade (for example, 0.3 mm) for semi-finishing.
And the cutting amount per tooth (for example, 0.05 mm) for the final finishing, and the theoretical, the above-mentioned cutting amount is achieved from the conditions such as the number of revolutions, the machining feed speed and the number of teeth. Possible value (eg, θa is 17-18 degrees, θ
b is 102 to 103 degrees).

The cutting blades 3k of the first cutting blade group 3 are coated with carbide, while the cutting blades 4k of the second cutting blade group 4 are formed of CBN (cubic boron nitride). Material, and the thickness of the cutting blade is the same as that of the cutting blade 3 of the first cutting blade group 3.
The cutting edge 4k of the second cutting edge group 4 is thinner than the cutting edge 4k of the second cutting edge group 4 than the cutting edge 3k of the first cutting edge group 3. Are more acutely angled. It should be noted that there is no difference between the cutting edge 3k of the first cutting blade group 3 and the tip protrusion amount of the cutting blade 4k of the second cutting blade group 4.

By rotating the rotary cutting tool 1 in the X direction shown in FIG. 2 while feeding it in the Y direction, the cutting allowance d shown in FIG. 1 is cut. Then
The medium finishing is performed by the first cutting blade group 3, and the final finishing processing is performed by the second cutting blade group 4 at the same time. That is, the intermediate finishing and the final finishing are performed at the same time, so that the number of steps can be reduced and the processing time can be significantly reduced.

The present invention is not limited to the above embodiment. Those having substantially the same configuration as those described in the claims of the present invention and having the same functions and effects belong to the technical scope of the present invention. For example, the number of the cutting edges 3k and 4k is not limited to three, and specific angles of θa and θb are also examples.

[0019]

As described above, the rotary cutting tool according to the present invention has a plurality of cutting blades of the first cutting blade group and a plurality of cutting blades of the second cutting blade group on the outer peripheral portion on the bottom side of the tool body. The blades are arranged at equal intervals, and the first cutting blade group and the second cutting blade group are arranged such that the intervals between adjacent cutting blades are unequal. The cutting amount of the second cutting blade group and the cutting amount of the second cutting blade group can be changed. For example, a cutting blade group having a large cutting amount is used as a medium finishing cutting blade, and a cutting blade group having a small cutting amount is used as a final finishing cutting blade. By doing so, semi-finishing and final finishing can be performed simultaneously in one process. By appropriately adjusting the moving range (interval) between the cutting edge of the first cutting edge group and the cutting edge of the second cutting edge group, the cutting amount of the first cutting edge group and the second The ratio of the cutting amount of the cutting blade group can be appropriately set. At this time, the cutting edge of the first cutting blade group is made of a carbide material, and the cutting edge of the second cutting blade group is made of CBN.
(Cubic boron nitride) material, and the cutting edge of the second cutting blade group is thinner than the cutting edge of the first cutting blade group, and the rake angle is more acute. This is more suitable for performing the semi-finishing with the first cutting blade group and performing the final finishing with the second cutting blade group.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of a rotary cutting tool according to the present invention.

FIG. 2 is a front view of the tool.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... rotary cutting tool, 2 ... tool main body, 3 ... 1st cutting blade group, 3k ... cutting blade, 4 ... 2nd cutting blade group, 4k ... cutting blade.

Claims (4)

[Claims] 1. A rotary cutting tool provided with a blade for contouring a workpiece according to a product shape, wherein said blade has a plurality of cutting blades arranged at equal intervals on a bottom side outer peripheral portion of a tool body. A first group of cutting blades is provided, and a second group of cutting blades is provided in which the number of cutting blades corresponding to the first group of cutting blades are arranged at equal intervals on the outer peripheral portion on the bottom side of the tool body. A rotating cutting tool, wherein the first cutting blade group and the second cutting blade group are arranged such that the intervals between adjacent cutting blades are unequal. 2. The rotary cutting tool according to claim 1, wherein the first cutting blade group and the second cutting blade group are arranged in the same manner.
The distance from the cutting edge of the first cutting edge group to the cutting edge of the second cutting edge group is from the cutting edge of the second cutting edge group to the cutting edge of the first cutting edge group in the rotation direction. A rotary cutting tool having a predetermined range wider than the interval of the rotary cutting tool. 3. The rotary cutting tool according to claim 2, wherein the cutting blades of the first cutting blade group are made of a carbide material.
The cutting edge of the cutting edge group is a CBN (cubic boron nitride) material. 4. The rotary cutting tool according to claim 2, wherein a cutting edge of the second cutting edge group is thinner than a cutting edge of the first cutting edge group, and A rotary cutting tool characterized in that the rake angle is more acute.