JPS5880114U

JPS5880114U - double-blade drilling tool

Info

Publication number: JPS5880114U
Application number: JP17557581U
Authority: JP
Inventors: 能上　進; 高田　義人; 糟谷　博
Original assignee: 三菱マテリアル株式会社
Priority date: 1981-11-26
Filing date: 1981-11-26
Publication date: 1983-05-31
Also published as: JPS628973Y2

Abstract

(57)【要約】本公報は電子出願前の出願データであるた
め要約のデータは記録されません。(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Brief explanation of the drawing]

第１図は先に提案した中心に切刃のないドリルの一例を
示す図でａはその底面視図、ｂはその側面図、第２図は
この考案の一実施例を示す図でａはその底面視図、ｂは
その側面図、第３図はこの考案の他の実施例を示す底面
視図、第４図は第３図の■内部の拡大側面図、第５図〜
第７図は夫々この考案のさらに他の各実施例を示す側面
図、第８図は第７図の底面視図である。１・・・・・・工具本体、２・・・・・・切刃チップ、
１３゜２３、　３３．　４３．　５３・・・・・・切刃
、１３ａ、２３ａ。３３ａ、　　４３ａ、　　５３ａ−−−−−−内端縁、
１３ｂ、２３ｂ。３３ｂ、　４３ｂ、　５３ｂ・・・・・・凸曲線部、１
３Ｃ１２３Ｃ，３３Ｃ，４３Ｃ，５３Ｃ・・・・・・凹
曲線部、１４・・・・・・すくい面、１５・・・・・・
切屑排出溝、０・・・・・・回転中心。補正　昭５７．１１．２２図面の簡単な説明を次のように補正する。明細書第７頁第１１行の「２０はドリル」を「２０−は
ドリル刃」ど補正する。明細書第７頁第１１行の「２４はばね」を「２４は′　
圧縮ばね」と補正する。Fig. 1 shows an example of the previously proposed drill without a cutting edge in the center, a is a bottom view, b is a side view, and Fig. 2 is a diagram showing an embodiment of this invention. Fig. 3 is a bottom view showing another embodiment of this invention, Fig. 4 is an enlarged side view of the interior of Fig. 3, Figs.
FIG. 7 is a side view showing still other embodiments of this invention, and FIG. 8 is a bottom view of FIG. 7. 1... Tool body, 2... Cutting tip,
13°23, 33. 43. 53... Cutting blade, 13a, 23a. 33a, 43a, 53a---inner edge,
13b, 23b. 33b, 43b, 53b... Convex curved portion, 1
3C123C, 33C, 43C, 53C... Concave curved portion, 14... Rake face, 15...
Chip discharge groove, 0...Rotation center. Amendment November 22, 1982 The brief description of the drawing is amended as follows. "20 is a drill" on page 7, line 11 of the specification is corrected to "20- is a drill blade.""24 is spring" on page 7, line 11 of the specification is replaced with "24 is'"
"compression spring".

Claims

[Scope of utility model registration request]

Two cutting blades 13 are provided at the distal end of the tool body 1 with inner edges 13a spaced apart from each other by an equal distance from the rotation center 0 of the tool body 1, and each of the cutting blades 13 is provided with an inner edge 13a spaced apart from the center of rotation 0 of the tool body 1. In addition, when the two-edged drilling tool is provided with a chip discharge groove 15 provided along the axial direction of the tool body 1, when each of the cutting edges 13 is viewed from the bottom, the cutting edges 13 are: It consists of three or more smooth convex curved parts 13b and smooth concave curved parts 13C formed alternately from the 1st rotation center 0 side toward the outer circumferential side of the tool body 1, and the convex curved parts 13b and the concave curved parts A two-blade drilling tool characterized in that the portion 13C is located on the same rotational direction side, and the convex curved portion 13b projects ahead of the concave curved portion 13C in the cutting rotational direction.