The Institute of Science and Technology, University of Tokyo
The Institute of Science and Technology, University of Tokyo
出版者
東京大学理工学研究所
雑誌名
東京大學理工學研究所報告
巻
3
号
11/12
ページ
335 - 341
発行年
1950-10-25
抄録(英)
Drilling spindles with precise ball bearings and special adjustable chucks were made for the purpose of using in bench boring machine. The spindles could be driven very silently at high speed without vibration, and have already been used in practice for over two years. With these spindles, the efficiency of drilling small holes in pillar-plates has increased by 200 %. Experimental investigations on the relations between drilling efficiency and rotating or feeding speed were carried out in the laboratory, and it is concluded that in order to drill. Small precise holes (0.3mm-1.5mm) efficiently, drills must be chucked with eccentricity less than about 0.005mm, and must be driven with high speed over 10,000rpm.