JP2001030107A - Axially rotating cutting tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an axially rotating cutting tool for preventing the falling off of a tip having a cutting edge fixed to a body from the body. SOLUTION: An outer peripheral blade 2 as a tip having a cutting edge 2a on a tip part is supported at the back surface opposite to cutting direction by a supporting part 5c, and the root portion of the rake face 2c (a cutting directional front surface) of the blade 2 is supported by a receiving part 5a. Consequently the blade 2 can be supported on a body 5 by the receiving part 5a formed on the root portion of the face 2c of the blade 2, even a rotating force (an arrow C) about the tip portion 5d of the supporting part 5c is applied in a direction for separating the blade 2 from the supporting part 5c and a bottom board part 5b, by applying cutting resisting force (an arrow B) to the edge 2a. Resultantly the blade 2 is prevented from separating from the supporting part 5c and the bottom board part 5b to falloff from the body 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an axial rotary cutting tool such as an end mill, and more particularly to an axial rotary cutting tool capable of preventing a chip having a cutting edge fixed to a body from falling off the body. It is about tools.

[0002]

2. Description of the Related Art In recent years, in order to increase the processing capability of hard-to-cut materials such as ceramic outer wall materials and aircraft carbon fiber materials (CFRP), high-quality materials that emphasize durability and quietness have been developed. Many shaft-shaped rotary cutting tools have been developed. Among such products, an axial rotary cutting tool in which a cutting edge is formed by a diamond tip has attracted particular attention. By adopting such high hardness chips,
Not only does cutting resistance decrease, enabling high-speed feed,
There is an advantage that the cutting noise is reduced and the working environment is improved.

FIG. 3 is a cross-sectional view of a body 51 showing a state of attachment of a chip 52 according to the prior art. Body 51
Is formed in the direction of the tip of the axial rotary cutting tool 50, and several chips 52 are fixed to the surface of the body 51. FIG. 3 shows two chips 5 having a substantially trapezoidal cross section on the body 51.
2 shows a state in which it is fixed. As shown in FIG. 3, the tip 52 fixed to the body 51 has a two-layer structure of a diamond plate 53 and a super hard alloy (super hard) 54, and cuts a work material (not shown). Cutting edge 52a
Is formed at the tip of the diamond plate 53.

[0004] A substantially arc-shaped blade groove 51a for accommodating and discharging chips during cutting is formed in the body 51, and a tip 52 is attached to one end of the blade groove 51a. Bottom portion 51b is formed substantially flat. From the end on the side opposite to the blade groove 51a of the bottom part 51b,
A support part 51c is formed substantially perpendicular to the bottom part 51b. The chip 5 is attached to the bottom portion 51b and the support portion 51c.
2 is soldered, so that the tip 52 is
1 is fixed.

[0005]

However, in the conventional rotary cutting tool 50 in which the tip 52 is fixed to the body 51 by such a configuration, the rotary rotary cutting tool 5
When 0 rotates in the direction of arrow R to start cutting, the tip 5
A cutting resistance acts on the cutting edge 52a at the tip of the second member in the direction of arrow S. Due to this cutting resistance, a rotational force is applied to the tip 52 in the direction of arrow T with the tip 51d of the support portion 51c as the center of rotation. Due to this rotational force, the back surface and the bottom surface of the chip 52 are separated from the support portion 51c and the bottom portion 51b, respectively, and there is a problem that the chip 52 falls off from the body 51.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and an axial rotary cutting tool capable of preventing a chip having a cutting edge fixed to a body from falling off the body. It is intended to provide.

[0007]

Means for Solving the Problems To achieve this object, an axial rotary cutting tool according to claim 1 has a tip having a cutting edge for cutting a work material, a body to which the tip is fixed, A supporting portion for supporting the chip, which is formed on a back surface of the body on the side opposite to the cutting direction of the chip, and a receiving portion for supporting the chip at a root of a front surface of the chip in the cutting direction. Are formed.

According to the shaft-shaped rotary cutting tool according to the first aspect of the present invention, the tip having the cutting edge at the tip end is supported by the supporting portion on the back side in the direction opposite to the cutting direction, and is received by the receiving portion in the cutting direction of the chip. The front base is supported.

A second aspect of the present invention is the axial rotary cutting tool according to the first aspect, wherein the body is provided with a blade groove for discharging chips.
The receiving portion is formed as a part of the body at a boundary between the blade groove and the rake face of the chip.

[0010]

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 (a)-
FIG. 1C is an external view of an end mill 1 as an example of an axial rotary cutting tool, and FIG. 1A is a left side view and FIG.
Is a front view, and FIG. 1 (c) is a right side view.

The end mill 1 is a milling cutter having an outer peripheral blade 2 and a bottom blade 3. A cylindrical shank 4 for attaching the end mill 1 to a collet chuck (not shown) of a cutting machine such as a milling machine is formed on one side of the end mill 1. A body 5 formed in a substantially rod shape extends below the shank 4, and the outer peripheral blade 2 and the bottom blade 3 as chips are fixed to the body 5. An arrow A illustrated above the shank 4 indicates a rotation direction at the time of cutting the end mill 1.

A total of five peripheral blades 2 are fixed to the side surface of the body 5, three on the surface shown in FIG. 1A and two on the surface shown in FIG. The outer peripheral blades 2 are arranged alternately on the surface shown in FIG. 1 (a) and the surface shown in FIG. 1 (c) from the shank 4 side of the body 5 to the bottom blade 3 side at regular intervals. Have been. Except for the outer peripheral blade 2 disposed at the lowermost stage, the direction of disposition of each outer peripheral blade 2 is not parallel to the axial direction of the end mill 1 in a side view, and the rotational direction becomes closer to the shaft toward the shank 4 side. It is fixed to the body 5 with a twist angle of about 15 ° in the direction inclined toward the side (arrow A).

On the other hand, the outer peripheral blade 2 disposed at the lowermost stage is disposed in a direction opposite to the other outer peripheral blades 2, and the end mill 1
The shaft is fixed to the body 5 with a twist angle of about 15 ° in a direction inclining toward the anti-rotation direction (reverse to the arrow A) as approaching the shank 4 side. When the end mill 1 is rotated by the cutting machine, the workpiece is cut along the outer peripheral surface on the side of the end mill 1 by the outer peripheral blade 2.

FIG. 2 is a sectional view of the body 5 taken along the line II-II in FIG. As shown in FIG. 2, the cross-sectional shape of the outer peripheral blade 2 is substantially trapezoidal, and has a two-layer structure of a diamond plate 6 and a super-hard alloy (super-hard) 7. A cutting edge 2 a for cutting a work material (not shown) is formed at the tip of the diamond plate 6.

On the outer peripheral surface side of the body 5 in the outer peripheral blade 2, the surface of the outer peripheral blade 2 is released from the cut finished surface of the work material in order to avoid unnecessary contact with the cut finished surface of the work material. A flank 2b is formed. In addition, a rake face 2c serving as a main body for cutting is formed on the front surface of the outer peripheral blade 2 in the cutting direction (arrow A). A cutting edge 2a is formed at a portion where the rake face 2c is connected to the flank 2b, and the workpiece is cut by the cutting edge 2a.

Rake surface 2c of outer peripheral blade 2 in body 5
On the side (the front side in the cutting direction), substantially arc-shaped blade grooves 8 for accommodating and discharging chips at the time of cutting are formed. When the end mill 1 is rotated, the cutting edge 2 of the outer peripheral edge 2 is
When a starts cutting the work material, chips are generated. The chips are rubbed against the rake face 2 c and are accommodated in the blade grooves 8, and are discharged to the shank 4 side (upward in FIG. 1) along the blade grooves 8.

The end of the blade groove 8 on the outer peripheral blade 2 side is formed so as to ride on the upper surface of the rake surface 2c of the outer peripheral blade 2 and is joined to the surface of the rake surface 2c in a smooth shape. The receiving portion 5a (part of the body 5) is formed by the blade groove 8 running on the upper surface portion of the rake face 2c. That is, the receiving portion 5a is formed at the base of the rake face 2c (the front side in the cutting direction) of the outer peripheral blade 2.

A substantially flat bottom plate 5b is connected to the lower end of the receiving portion 5a. An end of the bottom plate 5b on the side opposite to the blade groove 8 is substantially connected to the bottom plate 5b. A vertically extending support portion 5c is formed. The outer peripheral blade 2 is fixedly inserted into a concave portion of the body 5 surrounded by the receiving portion 5a, the bottom plate portion 5b, and the supporting portion 5c. Specifically, the outer peripheral blade 2 is provided with a receiving portion 5 formed on the body 5.
a, the bottom part 5b and the support part 5c are brazed.

As shown in FIG. 1C, a bottom blade 3 as a chip is fixed to the bottom surface of the body 5. The bottom blade 3 is fixed to the body 5 at a rake angle of about 15 ° with respect to the axis of the end mill 1. Like the outer peripheral blade 2, the bottom blade 3 has a two-layer structure of a diamond plate and a super-hard alloy (carbide), and the cutting blade for cutting the work material is formed at the tip of the diamond plate. . When the end mill 1 is rotated, the work material is cut by the bottom blade 3 along a plane perpendicular to the rotation axis.

Next, the operation of the end mill 1 according to one embodiment of the present invention at the time of cutting (action of force) will be described. First, the shank 4 of the end mill 1 is attached to a collet chuck (not shown) of a cutting machine. Next, a switch (not shown) of the cutting machine is turned on to rotate the end mill 1, and the end mill 1 is brought into contact with a work material to start a cutting operation.

As shown in FIG. 2, the end mill 1
When cutting is started by rotating in the direction, the cutting resistance force acts in the direction of arrow B on the cutting edge 2a at the tip of the outer peripheral blade 2 due to contact with the work material. Due to this cutting resistance, a rotational force centering on the tip portion 5d of the support portion 5c acts on the outer peripheral blade 2 in the direction of arrow C. Then, by the rotational force, the back and bottom surfaces of the outer peripheral blade 2 are supported by the support portion 5 c and the bottom plate portion 5.
b.

However, in the end mill 1 of this embodiment, since the receiving portion 5a is formed at the base of the rake face 2c (the front surface in the cutting direction) of the outer peripheral blade 2, the outer peripheral blade 2 is formed by the receiving portion 5a. 5 supported. Therefore, it is possible to prevent the outer peripheral blade 2 from peeling off from the support portion 5c and the bottom plate portion 5b and falling off from the body 5.

The receiving portion 5a is provided with a blade groove 8 and a rake face 2.
Since it is formed as a part of the body 5 at the boundary with the edge c, it is not necessary to separately provide a member for supporting the root portion of the rake face 2c (the front side in the cutting direction) of the outer peripheral edge 2.
Therefore, the number of parts of the end mill 1 can be reduced, and the manufacturing cost of the end mill 1 can be reduced.

As described above, the present invention has been described based on the embodiments. However, the present invention is not limited to the above-described embodiments, and various improvements and modifications can be made without departing from the gist of the present invention. Can easily be inferred.

For example, in this embodiment, the receiving portion 5a for supporting the outer peripheral blade 2 is formed at the base of the rake face 2c (the front surface in the cutting direction) of the outer peripheral blade 2, but a similar receiving portion is also provided for the bottom blade 3. It may be formed. According to such a configuration, the same effect as that of the outer peripheral blade 2 can be obtained in the bottom blade 3 as well.

In this embodiment, a total of five outer blades 2 are used.
The end mill 1 used for cutting a relatively thick work material provided with the above has been described. That is, the end mill 1 having a relatively long blade length, which is the length from one end of the entire outer peripheral blade 2 to the other end.
Was explained. However, the present invention may be applied to an end mill having a short blade length for thin objects, for example, an end mill provided with a total of three or two peripheral blades. According to such a configuration, the same effect as the end mill 1 having a long blade length can be obtained even in an end mill having a short blade length for a thin object.

[0027]

According to the shaft-shaped rotary cutting tool according to the first aspect of the present invention, the tip having a cutting edge at the tip end is supported by the supporting portion on the back surface in the direction opposite to the cutting direction, and the receiving portion cuts the tip. The base at the front of the direction is supported.
Therefore, even when the cutting force is applied to the cutting edge, even when a rotational force acts in a direction in which the tip is to be peeled from the support portion with the tip portion of the support portion as the center of rotation, the tip is formed at the base portion of the front surface of the chip. There is an effect that the chip is supported by the receiving portion and the chip can be prevented from peeling off from the body.

According to the axial rotary cutting tool of the second aspect, in addition to the effect of the axial rotary cutting tool of the first aspect, the receiving portion further includes a body at the boundary between the blade groove and the rake face. Therefore, there is no need to separately provide a member for supporting the root portion of the front surface of the insert in the cutting direction. Therefore, since the number of parts of the shaft-shaped rotary cutting tool can be reduced, there is an effect that the manufacturing cost of the shaft-shaped rotary cutting tool can be reduced.

[Brief description of the drawings]

1 (b) is an external view of an end mill according to an embodiment of the present invention, wherein (a) is a left side view, FIG. 1 (b) is a front view, and FIG. 1 (c) is a right side view. It is.

FIG. 2 is a sectional view of the body taken along line II-II in FIG.

FIG. 3 is a cross-sectional view of a body showing a fixed state of a chip in a conventional technique.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 end mill (shaft-shaped rotary cutting tool) 2 outer peripheral edge (tip) 2a cutting edge 2c rake face 3 bottom edge (tip) 5 body 5a receiving part 5c support part 8 blade groove

Claims (2)

[Claims] 1. A chip having a cutting edge for cutting a work material, a body to which the chip is fixed, and a support portion for supporting the chip formed on a back surface of the body in a direction opposite to the cutting direction of the chip. And a receiving portion for supporting the chip is formed at a root portion of a front surface of the chip in the cutting direction, the shaft-shaped rotary cutting tool having: 2. The body is provided with a blade groove for discharging chips, and the receiving portion is provided as a part of the body at a boundary portion between the blade groove and a rake face of the chip. A shaft-shaped rotary cutting tool characterized by being formed.