JPS6317607Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a throw-away cutter for cutting grooves, which has particularly improved cutting performance and is suitable for rough cutting.

Hitherto, as this type of groove cutting cutter, a brazing type cutter as seen in, for example, Japanese Patent Publication No. 51-23750 has been known. The groove cutting cutter disclosed in this publication is provided with an arc-shaped rake face that exhibits a convex arc in the groove width direction.

However, brazing type cutters are not economical due to re-grinding of the tool, so indexable type tools are increasingly being used, and this is becoming the trend of the times.

On the other hand, throw-away type groove cutting cutters usually use a polygonal plate-shaped throw-away tip, which creates a straight line contact with the workpiece, resulting in a large impact and is not suitable for rough cutting. It was hot. Further, a cutter having an arc-shaped rake face is also disclosed in, for example, Japanese Utility Model Application Publication No. 142685/1985. However, the tool disclosed in this publication uses the front and back surfaces of the throw-away tip, so the rake angle in the radial direction of the tool body is negative, resulting in large cutting forces and being unsuitable for rough cutting. It was hot.

For this reason, there is a demand for the development of a throw-away cutter for cutting grooves that uses as many corners as possible, and that also has an improved cutting edge configuration that can be used for rough cutting.

The present invention was developed in view of the above-mentioned points, and an even number of throw-away tips are arranged in a staggered manner on the outer periphery of the disc-shaped tool body, approaching the edges of the tool alternately. In a fixed throw-away cutter for cutting grooves, the cutting performance is improved by taking into consideration the shape and arrangement of the throw-away tips, and the cutter is particularly suitable for rough cutting.

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the rough cutting throw-away cutter according to the present invention will be described below with reference to the drawings.

1 to 3, reference numeral 1 denotes a disk-shaped tool body having a central mounting hole 2, and a throw-away tip 4 is mounted in a tip seat 3 provided on the outer periphery of the tool body.

This throw-away tip 4 has the following shapes:
It has a substantially triangular plate shape with three arcuate side faces 5, and a central mounting hole 6 is bored therein.
The throw-away tips 4 are arranged in the tool body 1 in a so-called staggered manner in which they alternately approach both side edges of the tool body 1.

Therefore, this throwaway tip 4 is
It is fixed to the tip seat 3 of the tool body 1 using its central mounting hole 6 with, for example, a screw 7,
In cutting, the arcuate side surface 5 side constitutes a rake surface, and the approximately triangular surface 8 side constitutes a flank surface.

The throw-away tip 4 is given an inclination angle to the arcuate side surface 5, and when attached to the tool body 1, the rake angle α in the radial direction is 0°, a regular angle (α=4° in the illustration). ). On the other hand, on the flank side, the mounting angle β with respect to the rotation direction is alternately in the forward and reverse directions. This forward and reverse direction means that, with the arcuate cutting edge 9 as a reference, the center part of the tool body 1 is deviated so as to make contact with the workpiece earlier than on both side edges. be. This is done in consideration of stabilizing the biting contact with the workpiece and also improving the discharge of chips from the chip pocket 10 to both side edges. In addition, with the throw-away cutter for cutting grooves of the present invention, the bottom surface of the groove to be machined becomes a concave circular arc, but this does not pose a particular problem in the case of rough cutting.

Also, what can be seen in Figures 4 and 5 is
This is a modified example in which the throw-away tip 4 is attached within the tip seat 3 of the cartridge 11. This is done in consideration of a large diameter cartridge, and the cartridge 11 is fixed by a mounting bolt 12 and a wedge piece 13 arranged on the chip pocket 10 side.

Furthermore, in order to increase the strength of the cutting edge of the throw-away tip 4, a chamfer (not shown) is formed at the apex portion thereof, and a narrow land (not shown) is provided along the arcuate cutting edge 9. It is also possible to do so.

With the thus constructed throw-away cutter for grooving of the present invention, the following grooving is performed, for example, as a T-groove preparation process.

The tool specifications are an outer diameter of 250mmφ, a blade width of 27mm,
The total number of staggered blades is 12, and the surface of throwaway tip 4 is made of P30 equivalent material.
It is coated with TiN. in this case,
Regarding the angles of the throw-away tip 4, the rake angle α in the radial direction was 4°, and the mounting angle β was 5°.

Then, a groove with a groove width of 27 mm and a groove depth of 50 mm was cut on a work material made of SS41 using the product of the present invention. The cutting conditions at this time are cutting speed 120
m/min, table feed 460 mm/min, and feed per tooth 0.5 mm/tooth.

As a result, by adopting the circular cutting edge 9, the product of the present invention has a small impact force when biting the work material, and the strength of the cutting edge is improved, so the feed rate can be reduced by 0.5
It is now possible to raise the blade to mm/blade.

On the other hand, with conventional side cutters having a straight cutting edge, the impact force when biting into the work material was large, and the corners of the cutting edge were easily chipped.
For this reason, the limits of conventional products were a cutting speed of 70 m/min, table feed of 110 mm/min, and feed per tooth of 0.2 mm/tooth. This is because in conventional products, it is necessary to enlarge the chip pocket for chip evacuation, and therefore the number of blades must be reduced.

For comparison, the aforementioned work material was cut using a tool with a negative rake angle α in the radial direction and other tool specifications the same as the product of the present invention. With this comparison product, cutting was stopped because the impact noise became high at a feed per tooth of 0.4 mm, but cutting edge chipping occurred in the throw-away tip 4. Furthermore, the above-mentioned workpiece material was cut using a tool with the mounting angle β of the throw-away tip 4 set to 0° and other tool specifications the same as the inventive product. There was a problem with the high-pitched impact noise during feeding.

As explained above, the present invention provides a throw-away cutter for cutting grooves incorporating the throw-away tip 4 having three arc-shaped side surfaces, and therefore has the following effects.

First, it is suitable for rough cutting. This is because the feed per tooth can be set to 0.5 mm, as is clear from the cutting test described above. That is, this is made possible based on the cutting edge configuration, arrangement, and shape of the throw-away tip 4.

Secondly, the attachment strength of the throw-away chip 4 is high, and its life can be expected to be extended. This is because the approximately triangular surface 8 of the throw-away tip 4 is attached so as to constitute a flank surface, so that cutting resistance is received in the direction of the thickness.

[Brief explanation of drawings]

FIG. 1 is a partial front view showing an embodiment of the throw-away cutter for cutting grooves according to the present invention, FIG. 2 is a cross-sectional view taken along the - line in FIG. 1, and FIG. FIG. 1 is a plan view, FIG. 4 is a partial front view showing a modified example, and FIG. 5 is a plan view thereof. 1... Tool body, 4... Throwaway tip, 5... Arc side surface, 6... Center mounting hole, 8...
...Approximately triangular surface, 9...Circular cutting edge ridge.

Claims (1)

[Claims for Utility Model Registration] On the outer periphery of the disc-shaped tool body 1, an even number of throw-away tips 4 are arranged and fixed in a staggered pattern so as to approach both edges alternately. In the throw-away cutter for use, the throw-away tip 4 is made of a substantially triangular plate shape having three arcuate side surfaces 5, and is attached by using its central attachment hole 6,
The arcuate side surface 5 side forms the rake face for cutting, and the substantially triangular surface 8 side forms the flank surface, and the rake face side has an inclination angle to form the rake face in the radial direction. The angle α is set to 0° or a regular angle, and on the flank side, the mounting angle β with respect to the rotation direction is alternately set in the forward and reverse directions.
A throw-away cutter for grooving, characterized in that the arcuate cutting edge 9 is deviated closer to the center of the tool body 1 than to both edges so as to accelerate contact with the workpiece.