PURPOSE: To improve the cutting efficiency by arranging cutting faces having two or more types of radiuses of curvature on the tip so that they are adjacent to each other, thereby simultaneously performing machining of a part of minimum radius of a recessed part and machining of a flat part.
CONSTITUTION: A part of R1 is formed to a minimum radius of curvature on the tip, and the radius R1-part is shaped constant up to an angle of attack θ3 of a part to be machined of the minimum radius of curvature. A part of radius of curvature R2(R2 R1) adjacent to the R1-part is added over a length L to form a diamond chase 1 to an angle of attack θ1 of the tip. As a result, machining of the part of the minimum radius of a recessed part and machining of a flat part can be performed simultaneously by cutting the part cut by the R1-part of the small radius of curvature by the R2-part of the large radius of curvature.
KAMIYAMA FUJIMASA
TSURU EIJI
NAGAYOSHI HARUYUKI
