JPS6419691U - - Google Patents

Description

【図面の簡単な説明】[Brief explanation of the drawing]

第１図はこの考案にかかる拡底掘削機の正面図
、第２図は拡底作業時における拡底掘削機の正面
図、第３図は拡底掘削機の底面図、第４図は拡底
作業時における拡底掘削機の底面図、第５図は底
蓋の底面図、第６図は軸孔形成のためのアースド
リル工法を示す説明図、第７図は拡底部の異常を
示す説明図である。 １…スプライン軸、２…駆動軸（スプラインパ
イプ）、３…ボデイ、８…掘削ビツト、１０…ク
ロスヘツド、１１…ガイドレール、１２…ビツト
軸、１５…油圧ジヤツキ。 Fig. 1 is a front view of the bottom-expanding excavator according to this invention, Fig. 2 is a front view of the bottom-expanding excavator during bottom-expanding work, Fig. 3 is a bottom view of the bottom-expanding excavator, and Fig. 4 is a bottom-expanding excavator during bottom-expanding work. FIG. 5 is a bottom view of the excavator, FIG. 5 is a bottom view of the bottom cover, FIG. 6 is an explanatory diagram showing an earth drilling method for forming a shaft hole, and FIG. 7 is an explanatory diagram showing an abnormality in the expanded bottom part. 1...Spline shaft, 2...Drive shaft (spline pipe), 3...Body, 8...Drilling bit, 10...Crosshead, 11...Guide rail, 12...Bit shaft, 15...Hydraulic jack.

Claims (1)

【実用新案登録請求の範囲】 (1) 軸孔内に挿入した掘削ビツトを拡径するこ
とによつて上記軸孔内に拡底部を掘削する拡底掘
削機において、上記掘削ビツトとともに回転する
駆動軸の先端に、掘削作業中には軸孔底部の中心
に上記掘削ビツトの回転中心を位置決めするため
に地中に差し込むビツト軸を突出させ、上記掘削
ビツトを引上げる際には、そのビツト軸を引込め
る油圧ジヤツキを取り付けたことをとくちようす
る拡底掘削機。 (2) ビツト軸が２枚羽根の先端形状をなすこと
を特徴とする実用新案登録請求の範囲第１項記載
の拡底掘削機。[Scope of Claim for Utility Model Registration] (1) A drive shaft that rotates together with the drilling bit in a bottom-expanding excavator that excavates an enlarged bottom part in the shaft hole by expanding the diameter of the drilling bit inserted into the shaft hole. At the tip of the bit, protrude a bit shaft that is inserted into the ground in order to position the center of rotation of the drilling bit at the center of the bottom of the shaft hole during excavation work, and when pulling up the drilling bit, the bit shaft is A bottom-expanding excavator equipped with a retractable hydraulic jack. (2) The bottom-expanding excavator according to claim 1, wherein the bit shaft has a tip shape of two blades.