JPH1110433A - Rotary cutting tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotary cutting tool which provides high work efficiency and is inexpensive by using a rotary tool to be mounted on a portable power tool in grinding. SOLUTION: A tool main body 1 is formed by a cup-shaped central part and a disk-like outer peripheral part which is extended outward from the central part. A plurality of cut-away parts 4 are arranged in a peripheral fringe part, and a cutter tip 7 is joined by engaging with the cut away part 4 to form a front cutting blade 8 on a side of a front end face 5. The cut away part 4 has a part which is wider than a width of an opening 6 in an outer peripheral fringe on an inner peripheral side.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
It provides a rotary cutting tool suitable for removing rust, removing beads such as steel frames, chamfering building exterior wall materials, and the like, and is particularly used by being attached to a portable electric tool or a portable pneumatic tool.

[0002]

2. Description of the Related Art Conventionally, whetstones and polishing cloths have been used as tools for chamfering steel materials, removing rust, beading welded parts such as steel frames, chamfering exterior wall materials for buildings, etc. by being attached to a portable power tool. Paper is used a lot. These tools are disk-shaped tools having a certain degree of flexibility, and are basically grinding tools.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide an inexpensive tool with excellent working efficiency by performing the above-mentioned work by cutting. In realizing this, safety in high-speed rotation is also considered.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and comprises a cup-shaped central portion and a disk-shaped outer peripheral portion extending outward from the central portion. A rotary cutting tool comprising a formed tool body, a plurality of notches arranged on a peripheral edge of the tool body, and a cutting edge chip engaged and joined to the notch, The cutting edge tip has a front cutting edge formed on a front end surface side of the tool body. Also,
The notch has a portion wider on the inner peripheral side than the width of the opening on the outer peripheral edge, and the cutting blade tip is joined in a state of being engaged with the wider portion. Further, the front cutting edge has a front cutting edge angle of 0.5 ° to 5 ° and a rake angle of 0 ° to 45 °.

[0005]

Next, an embodiment of the present invention will be described with reference to the drawings.

In FIGS. 1 and 2, the tool body 1 is formed by a central portion having a cup shape and an outer peripheral portion having a disk shape extending outward from the cup portion. 2 are drilled. From the outer peripheral edge of the tool body 1, slits 3 are radially arranged at a predetermined length in the center direction. The central portion in the shape of a cup serves not only as a storage space for mounting bolts when the present rotary cutting tool is mounted on the portable power tool, but also has an effect of giving rigidity to the central portion of the tool body 1. On the other hand, the slit 3 absorbs the undulation of a thin plate that is easily deformed into an irregular shape,
The outer peripheral portion has an appropriate flexibility, and has an effect of preventing resonance of a cutting sound when the tool is used. And such a tool main body 1 is easily obtained by press.

A notch 4 is provided between the slits 3 on the periphery of the tool body 1. The notch 4 is formed so as to penetrate backward from the front end face 5 of the tool body 1 in the thickness direction, and is formed so as to present a tapered space that gradually becomes wider than the opening 6 in the radial direction. I have. Therefore, the opening 6
Becomes the narrowest width w. The notch 4 engages with the cutting edge chip 7 having a trapezoidal shape in a front view, and is brazed.
The general rotation speed of a portable power tool is 8000 to 1000
Since the rotation speed is 0 rpm, the cutting speed is higher than 3000 m / min for a rotary cutting tool having a diameter of 100 mm. Even if the joining may be loosened due to cutting heat during use, the rotary cutting tool has a small width w of the opening 6 so that the cutting edge chip 7 can be scattered against the centrifugal force. Preventing or delaying the scattering time allows time to be noticed.

FIG. 3 is an enlarged view related to the cutting blade tip 7. Since the cutting speed is high,
Super hard tool materials such as cemented carbide and cermet are preferred. The cutting edge chip 7 is overhanged and joined to the front of the front end face 5 to form a front cutting edge 8 at its tip. At this time, the front cutting edge angle α of the front cutting edge 8 is formed at 0.5 ° to 5 °, and the rake angle β of the front cutting edge 8 is formed at 0 ° to 45 °.

According to the experiments of the present inventors, the front cutting angle α
By providing a small number, the disadvantage that the entire length of the front cutting edge 8 comes into contact with the workpiece to increase the cutting resistance or induce chatter vibration is eliminated. On the other hand, when the front cutting edge angle α exceeds 5 °, the corner portion of the cutting edge tip 7 prominently protrudes, so that rust removal is not sufficiently performed or cutting streaks are noticeable on the machined surface. In addition to corner loss. With respect to the rake angle β, a good sharpness was obtained at a positive rake angle of 0 ° or more and 45 ° or less. However, if the angle exceeds 45 °, the rake angle is too large and the cutting edge strength is reduced, so that it is not recommended.

[0010] With the above configuration, it is possible to provide a rotary tool which is far less expensive than a conventional grindstone. Since it is possible to cut deeper than grinding and does not clog like a grindstone, it is possible to work with high efficiency. Since there is no dust generated by grinding, the working environment is improved.

FIGS. 4 and 5 show other embodiments of the present invention, in which the same portions are denoted by the same reference numerals. 4A, as shown in FIG. 4A, an inner peripheral portion extending at the same width as the width w of the opening 6 at the outer peripheral edge, and a semi-elliptical portion extending rearward in the rotation direction are formed. It has a notch 4 of combined shape. It penetrates in the thickness direction as shown in FIG. The cutting blade tip 7 is joined to the notch 4 with a projection that engages with the semi-elliptic portion of the notch 4. These projections prevent the cutting blade tip 7 from scattering in the unlikely event of centrifugal force.

FIG. 5A is the same as FIG. 4A in a front view as shown in FIG. 5A, but as shown in FIG. A notch step is formed without penetrating in the thickness direction. As a result, the resistance to the thrust force is strengthened, and the joining of the cutting blade tip 7 is further strengthened.

[0013]

According to the present invention, the rotary tool mounted on the portable power tool is realized by cutting.
Rotary cutting tools can be provided at low cost. In realizing the cutting tool, the opening width of the outer peripheral edge of the notch is narrowed to prevent the cutting edge chip from scattering. Since it can be used with a deeper cut than grinding and does not clog like a grindstone, work such as chamfering steel materials, removing rust, beading welded parts such as steel frames, chamfering building exterior wall materials, etc. Become highly efficient. Since there is no dust generated by grinding, the working environment is improved.

[Brief description of the drawings]

FIG. 1 is a front view showing an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 (a) is an enlarged view of (a) of a blade tip portion of FIG. 1;
(B) is a right side view, and (c) is a plan view.

4A and 4B show another embodiment of the present invention, wherein FIG. 4A is a front view of a blade tip portion, and FIG. 4B is a right side view.

5A and 5B show another embodiment of the present invention, wherein FIG. 5A is a front view of a blade tip portion, and FIG. 5B is a right side view.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Tool main body 4 Notch 6 Opening 7 Cutting edge tip 8 Front cutting edge w Width of opening α Front cutting edge angle β Rake angle

Claims (3)

[Claims] 1. A tool body formed by a cup-shaped central portion and a disk-shaped outer peripheral portion extending outwardly therefrom, and a plurality of tools disposed on a peripheral portion of the tool body. And a cutting edge chip that is engaged with and joined to the notch, and a front cutting edge is formed on the front end face side of the tool body. Characterized rotary cutting tool. 2. The notch has a portion wider on the inner peripheral side than the width of the opening on the outer peripheral edge, and the cutting edge tip is joined in a state of being engaged with the wider portion. The rotary cutting tool according to claim 1, wherein: 3. The front cutting edge angle of the front cutting edge is 0.5 ° or more.
The rotary cutting tool according to claim 1 or 2, wherein the rake angle is at 5 ° and the rake angle is at 0 ° to 45 °.