JPH03122190U

JPH03122190U -

Info

Publication number: JPH03122190U
Application number: JP3092690U
Authority: JP
Priority date: 1990-03-28
Filing date: 1990-03-28
Publication date: 1991-12-13

Description

[Brief explanation of drawings]

第１図は本考案の一実施例の一部断面側面図、
第２図はその実施例の平面図、第３図はボタンチ
ツプの正面図、第４図は第１図乃至第３図の実施
例の作用を示す一部断面側面図、第５図は従来技
術の一部断面側面図、第６図はその従来技術の平
面図、第７図は弾丸型チツプの正面図、第８図は
第５図及び第６図の従来技術の問題点を説明する
一部断面側面図である。１，１０……インナーコンビネーシヨンビツト
、１ｓ，１２……ビツト端面、２……水溝、３，
３ｃ，３ｅ……弾丸チツプ、４ｃ，４ｅ……水孔
、１４……ビツト端面周縁部、１６……ボタンチ
ツプ、Ｒ……硬岩。 FIG. 1 is a partially sectional side view of an embodiment of the present invention;
Fig. 2 is a plan view of the embodiment, Fig. 3 is a front view of the button chip, Fig. 4 is a partially sectional side view showing the operation of the embodiment of Figs. 1 to 3, and Fig. 5 is a conventional technique. 6 is a plan view of the prior art, FIG. 7 is a front view of the bullet-shaped chip, and FIG. 8 is a diagram illustrating the problems of the prior art shown in FIGS. 5 and 6. It is a partial cross-sectional side view. 1, 10... Inner combination bit, 1s, 12... Bit end face, 2... Water groove, 3,
3c, 3e...Bullet chip, 4c, 4e...Water hole, 14...Bit end face periphery, 16...Button chip, R...Hard rock.

Claims

[Scope of utility model registration request]

In an outer bit used in boring work using a rotary percution machine in anchor work and ground improvement work, a bullet tip with a bullet-shaped part exposed on the end face of the bit is placed in the center of the end face of the bit. An inner bit characterized in that, on the peripheral edge of the end face and between the water grooves, button tips whose exposed portions on the end face of the bit are flatter in shape than bullet tips are arranged at equal intervals.