Ball end mill

Abstract

A ball end mill enabling an increase in machining efficiency, wherein a pair of roughly semi-spherical ball edges (12a) and (12b) are formed on an edge part (3) at the tip thereof symmetrically with respect to the axis thereof, and the area of the edge part (3) including at least the ball edges (12a) and (12b) is formed of a hard sintered body (PCBN). Also, the faces of the ball edges (12a) and (12b) are formed by spiral gashes (14a) and (14b), and the helix angles of the spiral gashes (14a) and (14b) are formed at approximately 20 DEG. Since the ball edges (12a) and (12b) are formed of the hard sintered body having high hardness characteristic and formed in a twisted shape, the ball end mill can cut with a large depth of cut and at high speeds to increase the machining efficiency of the ball end mill.

Description

technical field [0001] The present invention relates to a ball end mill, and more particularly, to a ball end mill capable of improving machining efficiency by constituting a cutting edge with a hard sintered body. Background technique [0002] In the profiling of molds and the like by machine tools such as machining centers, ball nose end mills made of cemented carbide are generally used, but when machining molds that have been quenched for longer life, The cutting edge of the ball nose end mill wears faster and the tool life is shortened. In addition, although the life of the ball end mill can be extended by making the depth of cut shallower, in this case, the machining time for performing predetermined machining increases, resulting in a corresponding decrease in machining efficiency. In view of this, in recent years, ball nose end mills using a sintered cubic boron nitride (PCBN) body having high hardness for the cutting edge have been adopted in order to reduce wear of...

AI Technical Summary

Problems solved by technology

[0005] However, in the above-mentioned ball nose end mill, the cutting edge is formed in a straight line when viewed in the axial direction, so the cutting resistance during cutting is large, and it is not possible to perform deep cutting or high-speed cutting.

Therefore, there is a problem that sufficient machining efficiency cannot be obtained in a structure in which a plate member having a double-layer structure is welded as a cutting edge to the corner portion of the ball end mill.

Images