JPH08118104A - Tool - Google Patents

Abstract

PURPOSE: To perform finish cutting and enable mirror finishing of the cut surface simultaneously by making the back clearance angle in the lower part except for the upper part approaching a tip cutting edge in a tip made of tungsten carbide alloy larger than the back clearance angle of this upper part. CONSTITUTION: The front end 21 of a cutting tool 15, that is, the front end 21 of a shank 16, tip 18 and a diamond sintered body 19 is formed at a back clearance angle of about 20 deg., forming the land section 21a of the front end 21. This land section 21a is formed into an arc face having a radius of about 2mm in a plan view, and the whole area of this arc face is formed so that the back clearance becomes about zero (0) deg., and vertical width, that is, width from a tip cutting edge 20 to a lower part is ranged from 0.2mm to 0.5mm. The contact of the land section 21a with the cut face 11b directly after cutting by means of this tip cutting edge 20 mirror-finishes this cut face 11b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cutting tool for cutting a light alloy material or an iron material, and more particularly to a cutting tool for cutting a disk surface of an aluminum alloy wheel into a mirror surface.

[0002]

2. Description of the Related Art As a conventional cutting tool, there is one shown in FIG. In FIG. 5, reference numeral 1 denotes a bite, which is formed by forming the tip (right end) of the shank 2 made of steel into a V-shape in plan view with the width becoming gradually smaller toward the tip, and notching the upper surface of the tip in a step shape. To form a chip seat 3, and a chip 4 made of cemented carbide is fixed to the chip seat 3 by brazing. The front clearance angle γ of the front end 6 of the cutting tool 1 is formed to be about 20 degrees from the tip cutting edge 5 toward the lower end, and the rake angle α of the rake face 7 formed on the upper surface of the tip end portion of the tip 4 is α. Is
It is formed to be about 10 degrees.

[0003]

As shown in FIG. 6, in the above-mentioned conventional one, when the outer surface 11a of the disk portion 11 of the aluminum alloy wheel 10 is finish-cut by the cutting tool 1, the cutting surface 11b is cut. Fine irregularities remain. Therefore, the cutting surface 11b has to be buffed to be finished as a boundary surface, which requires a lot of time and labor for the buffing and requires a dedicated buffing machine, which increases equipment cost, space, etc. was there. It is an object of the present invention to obtain a new cutting tool that eliminates defects by finishing cutting with a cutting tool and finishing the cutting surface at the same time.

[0004]

The present invention is configured as follows in order to achieve the above object. That is,
A tip made of cemented carbide is fixed to the tip of the shank, and the tip has a front clearance angle of about zero degrees at the upper end approaching the tip cutting edge, and the front clearance angle of the lower portion excluding the upper end is less than zero degrees. It is configured to be large. In this case, the vertical width of the upper end portion at which the front clearance angle is about 0 degree is about 0.2 mm to
It may be 0.5 mm. Further, it is preferable that the tip cutting edge portion of the tip is formed of a diamond sintered body.

[0005]

Embodiments of the present invention will be described below with reference to the drawings. In the drawings, FIG. 1 is a plan view of a cutting state showing an embodiment of the present invention, FIG. 2 is a plan view of a cutting tool according to the present invention, and FIG.
2 is a side view of FIG. 2, and FIG. 4 is an enlarged side view of essential parts in a cutting state according to the present invention. In FIG. 1, reference numeral 10 is a wheel made of an aluminum alloy which is a processed material, and is formed by integrally forming a disc portion 11 and a rim portion 12. 15 is the disc portion 1
It is a cutting tool for finishing cutting the outer surface 11a of No. 1 to a predetermined size.

As shown in FIGS. 2 and 3, the cutting tool 15 is formed by integrally fixing a tip 19 to the tip of a shank 16. The shank 16 is formed by a steel material such as tool steel into a V-shape in plan view having a tip portion (right end portion) which gradually becomes narrower toward the tip, and the top surface of the tip portion is notched in a stepped shape to form a tip seat 17 This tip seat 17
Then, the tip 18 made of cemented carbide is fixed by brazing.

The tip 18 is formed in a plate shape having a thickness T of about 6 mm, and has a rake angle α of about 1 on the upper surface of its tip.
A notch is formed so as to be 0 degree, and a thin plate-shaped diamond sintered body 19 is fixed by brazing to the tip of the notch 18a. The tip cutting edge 20 is formed as a 2 mm arc surface.

Further, the front end 21 of the cutting tool 15, that is, the shank 16, the tip 19, and the front end 21 of the diamond sintered body 19 have a front clearance angle γ of about 20 degrees, and the front end 2
1 land portion 21a (FIG. 4) is formed. The land portion 21a is an arc surface having a radius of about 2 mm in a plan view, and the front clearance angle γ is set to about zero degree over the entire arc surface, and the width L in the up-down direction, that is, the tip cutting edge 20 downward. The width to go is set in the range of 0.2 mm to 0.5 mm. According to the experiment, the vertical width L of the land portion 21a is 0.2 m.
When the width is less than m, the cutting surface becomes a rough surface and cannot be finished as a mirror surface, and when the width L exceeds 0.5 mm, the cutting tool 15 is used.
Causes vibrations during cutting, causing wavy patterns on the cutting surface, making mirror finishing difficult.

In FIG. 1 and FIG. 2, 22 is an air discharge nozzle and 23 is a cutting water discharge nozzle, both of which are bites 1.
5, the air discharge nozzle 22 is blown toward the cutting surface 11b immediately after being cut from the lower side of the backward direction of the cutting tool 15 so that the chips are mainly directed in the direction opposite to the cutting surface. Scatter to prevent chips from coming into contact with the cutting surface 11b. Further, the cutting water discharge nozzle 23 sprays from the lower side of the backward direction of the cutting tool 15 toward the tip cutting edge 20 to mainly cool the tip cutting edge 20 part.

According to the above embodiment, as shown in FIG.
For example, when the outer surface 11a of the disk portion 11 of the aluminum alloy wheel 10 is cut by the cutting tool 15, the tip cutting edge 20
Land 21a on the cutting surface 11b immediately after being cut by
Contact each other and finish the cutting surface 11b as a boundary surface. Therefore, a dedicated buffing machine is unnecessary. In addition,
In this example, air is blown to the contact portion of the land portion 21a to cool the land portion 21a, and the cutting surface 11
It prevents chips from entering b.

[0011]

As is apparent from the above description, according to the present invention, the cutting material can be finished and cut to a predetermined size with the cutting tool, and at the same time, the cut surface can be finished to be a mirror surface, so that a dedicated buffing machine is unnecessary. As a result, the facility cost and space can be reduced, and the finishing process can be performed quickly.

[Brief description of drawings]

FIG. 1 is a plan view of a cutting state showing an embodiment of the present invention.

FIG. 2 is a plan view of a cutting tool according to the present invention.

FIG. 3 is a side view of FIG.

FIG. 4 is an enlarged side view of essential parts in a cut state according to the present invention.

FIG. 5 is a side view of a cutting tool showing a conventional example.

FIG. 6 is a side view showing a cutting state of a conventional example.

[Explanation of symbols]

 10 Wheel 11 Disk Part 11a Outer Surface 11b Cutting Surface 15 Shank 16 Shank 17 Tip Seat 18 Tip 18a Notch 19 Diamond Sintered Body 20 Tip Cutting Edge 21 Front End 21a Land Part α Rake Angle γ Front Clearance Angle 22 Air Discharge Nozzle 23 Cutting Water Discharge nozzle

Claims (3)

[Claims] 1. A tip made of cemented carbide is fixed to the tip of the shank, and the tip has a front clearance angle of about zero degrees at the upper end approaching the tip cutting edge, and the lower front clearance excluding the upper end. A bite whose angle is larger than zero. 2. The cutting tool according to claim 1, wherein the vertical width of the upper end portion at which the front clearance angle is approximately zero degrees is approximately 0.2 mm to 0.5 mm. 3. The tip cutting edge portion of the tip is formed of a diamond sintered body.
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