JPS6024501Y2 - Cemented carbide cutting blade - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an improvement of a rotary round cutting blade whose outer circumferential blade portion is made of hardened metal.

In general, this type of cutting blade includes (a) a so-called peel-shaped cutting blade C1 in which the entire body 1 of the cutting blade is made of cemented carbide (first
(see figure), and (b) only the blade part 2 is made of cemented carbide, the disc-shaped blade part 2 is heat-fixed to the upper surface of the steel base metal 3, and the angled metal ring 4 is attached to the screw 5. By pressing with
Two types are known, such as one in which the blade portion 2 is firmly fixed, and one in which only the blade portion is made of cemented carbide (C2) (see Fig. 2).

In the conventional general cutting blades C1 and C2, the shape of the cutting edge is as shown in FIG.
It is configured to be pointed at an angle of ~25°.

That is, in the cutting blades C1 and C2, the side surface 6 is orthogonal to the axis l, and the angle is 15 to 25 degrees with respect to the side surface 6.
A cutting edge 8 is provided at the intersection with the inclined outer circumferential surface 7.

However, in the cutting blades C1 and C2 having the above configuration, the angle between the outer circumferential surface 7 and the side surface 6 is as small as 15° to 250°, that is, the blade angle is as small as 15° to 25°, and the cutting edge portion is sharp. Therefore, there were problems in that the strength of the cutting edge 8 was low, chipping occurred frequently, and the service life was short.

This invention was made in order to solve the above-mentioned problem, and its purpose is to provide a cemented carbide cutting blade that can significantly reduce the occurrence of chipping at the cutting edge.

First, let's talk about the characteristics of this invention.The characteristics of this invention are based on various experimental results.

In other words, according to various experimental results, even if the outer circumferential surface is formed parallel to the axis, the cutting edge can be maintained within a certain range, even if the outer circumferential surface is not inclined to make the cutting edge sharp. It was found that the machinability did not deteriorate.

Here, "within a certain range" means within 0.27 rrIn.

That is, the greatest feature of this invention is that the range within 0.2 inclination from the cutting edge on the outer circumferential surface is made into a narrow surface parallel to the axis.

In this case, one side surface constituting the narrow surface and the cutting edge is perpendicular to the axis, and the other side surface has a first inclined surface starting from the narrow surface and a second inclined surface continuing therefrom. It consists of an inclined surface.

Note that the inclination angle θ of the first inclined surface and the inclination angle of the second inclined surface are degrees of inclination from a plane orthogonal to the axis.

0≦to〈 satisfies the condition. In this way, if the area within 0.2rrvn from the cutting edge on the outer circumferential surface is formed parallel to the axis, the strength of the cutting edge can be increased compared to the case where the outer circumferential surface is inclined. chipping can be prevented.

Moreover, since the parallel range is 0.2 nvn or less, the cutting performance of the cutting edge does not deteriorate.

Note that if the parallel range is made too small, the strength of the cutting edge will inevitably decrease.

Therefore, the range needs to be 0.05 mm or more.

An embodiment of this invention will be described below with reference to FIGS. 6 to 8.

The cutting blade C3 shown in these figures has a so-called solid body whose entire body 14 is made of cemented carbide, and is used for cutting the lead wires 11 in the printed circuit board 9 as described above.

Also in this cutting blade C3, as shown in FIG. 7, a cutting blade 80 is formed at the intersection of one side surface 60 perpendicular to the axis 1 and the outer circumferential surface 13.

However, in this cutting blade C3, the outer circumferential surface 13 is formed parallel to the axis 1 without being inclined, and its width is set to 0.05rIrIIt to 0.2Nn.

Further, an outer circumferential portion 700a of the other side surface 700 is formed parallel to the side surface 60, so that a range of width W from the outer circumferential surface 13 toward the axis 1 side has a constant thickness t.

This thickness t is, of course, the same as the width of the outer peripheral surface 13, and -
The blade width W is set to 0.3 to 3.011rIrL.

Note that a portion of the side surface 700 following the outer peripheral portion 700a is an inclined surface 700b forming an angle of 15° to 25° with the side surface 60.

Therefore, in the cutting blade C3 having the above configuration, the outer circumferential surface 13 is made parallel to the axis 1, and the angle formed with the side surface 60 is 90°.
As a result, the strength of the cutting edge 80 is improved, and the occurrence of chipping on the cutting edge 80 can be significantly reduced.

In addition, in this example, the thickness of the cutting edge portion was set to 0.0
5rrrIn~0.2Trr! Since it is set to n, even if chipping 12G as shown in FIG. 8 occurs, there is no need for re-grinding.

For example, when the lead wires 11 on the printed circuit board 9 were cut using the cemented carbide cutting blade C3 in the same manner as described above, the conventional ones C□ and C2 required re-grinding after 700 to 1,000,000 wires. On the other hand, this cutting blade C3 has a
It was possible to cut up to 2.5 million pieces without re-grinding.

Moreover, FIG. 9 shows another embodiment of this invention.

This cutting blade C1 cuts the outer peripheral part 70a of the side surface 70 into the inclined surface 7.
It is inclined at an angle θ□ smaller than the inclination angle θ2 of 0b.

Therefore, the thickness of the cutting edge portion gradually increases from the outer circumferential surface 13 toward the axis, but in this case as well, the width of the outer circumferential surface 13 is made wider than 0.05 mm, and the outer circumferential portion 70a
If the thickness at the intersection between the outer circumferential portion 70a and the inclined surface 70b is set to 0.2 mm or less, there is no need for re-grinding until the outer peripheral portion 70a is completely removed.

Although the above embodiment has been described with respect to a so-called hollow-shaped cutting blade, it goes without saying that this invention can also be applied to a cutting blade in which only the blade portion is made of cemented carbide.

[Brief explanation of drawings]

Figures 1 and 2 are front sectional views of the entire cutting blade showing conventional examples of this type of cutting blade, Figure 3 is an enlarged view of the main parts showing the shape of the blade edge of the conventional example, and Figure 4 is of this type. 5 is a front view showing an example of how the cutting blade is used, FIG. 5 is a diagram showing the occurrence of chipping in a conventional example, FIG. 6 is a front sectional view of the entire cutting blade showing an embodiment of this invention, and FIG. FIG. 8 is an enlarged view of the main part showing the shape of the cutting edge of the embodiment, FIG. 8 is a view showing the occurrence of chipping in the same embodiment, and FIG. 9 is an enlarged view of the main part of another embodiment of this invention. 13... Outer peripheral surface, 60... One side of the cutting blade, 80... Cutting blade.

Claims (1)

[Scope of claim for utility model registration] The cutting blade on the outer periphery is a rotary round cutting blade made of cemented carbide,
A cutting blade made of cemented carbide, characterized in that the cutting edge portion is configured along the following (4) and (B). (4) The cutting blade is a surface that is perpendicular to the axis, is parallel to the surface that forms one side of the cutting blade, and has a width of 0.05 to 0.2rrrm. It must be installed at the intersection with a narrow surface. (B) The other side surface of the cutting blade is composed of a first sloped surface that starts from the narrow surface and slopes at an inclination angle θ1, and a second sloped surface that continues therefrom and slopes at an inclination angle θ2. has been done. However, the above two inclination angles θ1 and θ2 are degrees of inclination from a plane perpendicular to the axis, and 0≦θ1 and θ2
Satisfy the following conditions.