JPS6113216Y2 - - Google Patents

Description

[Detailed description of the invention] The invention relates to a spherical counterbore cutter, and in particular,
Accurate spherical counterbore cutting can be performed with both cutter heads formed at both ends of the central shaft.

Conventionally, this type of spherical counterbore cutter has a cutting blade tip with an arcuate cutting edge ridged to it by brazing along a spherical body.

Therefore, since the cutting edge tip is a rectangular plate-like one with an arcuate side surface, cutting efficiency is poor due to brazing stress and changes in feed or depth of cut in the axial and radial directions. However, there were problems such as difficulty in forming the cutting edge during re-grinding.

For this reason, it has been desired that this type of spherical counterbore cutter be made into a throw-away type in order to improve production efficiency and eliminate the need for re-grinding.

The present invention was developed in view of the above-mentioned points, and provides a spherical counterbore cutter in which the cutting blade tip is made into a throwaway type, the cutting blade configuration is rationalized, and internal spherical counterboring is possible. It is.

Hereinafter, one embodiment of the spherical counterbore cutter of the present invention will be described with reference to the drawings.

In FIGS. 1 and 2, reference numeral 1 indicates a central shaft, and cutter heads 2 are formed at both ends thereof to bulge out in the diametrical direction.

This cutter head 2 has two parts on its outer periphery.
Two cutout recesses 3 are provided, and a chip seat 4 having two side walls is formed in the cutout recess 3.

A cutting blade tip 5 is fixed in the tip seat 4 by a screw 7 using a central mounting hole 6 thereof. This cutting edge tip 5 is a substantially triangular plate consisting of three arcuate side surfaces, and its diametrical position is uneven on the rotation locus so that the cutting edge 8 partially cuts the spherical surface. It is something that is ranked. Furthermore, mounting holes 10 are formed on both end surfaces of the cutter head 2, respectively.

The spherical counterbore cutter constructed in this way is supported at both ends by the rotation transmission shaft 9, and by the axial movement of the rotation transmission shaft 9, the cutting blade tip 5 on the moving direction side performs spherical counterboring. It is.

That is, the workpiece 11 is a cylindrical body with a window opening as shown in FIG. 3, and the processing order is as follows:
As shown in FIGS. 4 and 5, the work material 1
Countersinking is performed on both sides of 1. In this case, the cutter is supported at both ends by the rotation transmission shaft 9 after being inserted through the window portion.

Therefore, in the illustrated case, three cutting edges can be used for the cutting edge tip 5 due to the relief angle provided, and the first
As is clear from the figure, it can be incorporated into the cutter head 2 without impairing its rigidity. Additionally, due to the partial sharing of cutting, the chattering vibration that previously occurred has been eliminated, improving cutting characteristics.

Next, an example of cutting FC30 using the spherical counterbore cutter of the present invention will be explained. The tool specification is that the cutting edge radius is set to 41 mm, and the first
As shown in the drawings and FIG. 2, this is a so-called two-blade type in which the cutting blade tip 5 is deviated not only toward the outer circumference but also toward the center. In this case, the cutting edge tip 5
is, its inscribed circle x thickness is 9.53mmφ x 4.76mm, and 7
These thighs are designed to have a relief surface of ゜.

The cutting conditions were a cutting speed V of 60 m/min and a feed rate f of 0.05 mm/tooth. As a result of cutting, the finished surface roughness was as shown in FIG. 6a. On the other hand, in the comparative brazed products, the results shown in FIG. 6b were that the product of the present invention was clearly superior. This is due to the fact that with conventional brazed products, it was difficult to achieve precision when grinding circular arc cuts due to the difficulty of supporting the cutter, and the cutting resistance was large due to the cutting edge length covering the entire area of the cutting tip. This is because the problems such as the fact that the axial movement of the rotation transmission shaft changed due to re-grinding, making it difficult to secure an appropriate depth of cut, were improved. Furthermore, since the degree of freedom in selecting the material of the cutting edge 5 has been expanded, for example, cermet can be used, and the finished surface roughness has been improved.

As explained above, in the present invention, the cutter head is supported by rotating shafts from both ends, and cutting is partially shared by the cutting blade tips screwed together in a minimum space. Since the cutting edge of the blade tip is also indexed, the problem of re-grinding can be eliminated, and the cutting efficiency is also improved.

[Brief explanation of the drawing]

Fig. 1 is a front view showing a sectional view of the lower half of an embodiment of the spherical counterbore cutter of the present invention, Fig. 2 is a side view thereof, Fig. 3 is a perspective view showing the workpiece, and Fig. 4 Figures 5 and 5 are partially cutaway front views illustrating the processing order of the spherical counterbore cutter, and Figures 6a and b show the finished surface roughness, where a is the product of the present invention; b is based on a conventional product. 1...Central axis, 2...Cutter head, 3...
Notch recess, 4... Chip seat, 5... Cutting blade tip.

Claims (1)

[Claims for Utility Model Registration] A cutter head 2 that bulges out in the diametrical direction is formed at both ends of the central shaft 1.
A plurality of cutting blade tips 5 for cutting a spherical surface are installed in a notch recess 3 provided on the outer peripheral edge of the cutter head 2 in a positional relationship such that they share cutting duties on the rotation locus, and the cutter head 2 is mounted on both end surfaces. Rotation transmission shafts 9 are installed in mounting holes 10 drilled in each
A spherical counterbore cutter is supported at both ends by being inserted into the cutter, and is configured such that the cutting blade tip 5 on the moving direction side cuts by the axial movement of the rotation transmission shaft 9, The cutting blade tip 5 is made of a substantially triangular plate-like member with three arcuate side surfaces, and its central mounting hole 6 is used within the tip seat 4, which has two side walls provided in the cutout recess 3 of the cutter head 2. A spherical counterbore cutter characterized by being fixed with screws.