| 摘要 |
515,599. Drilling machines. ARCHDALE & CO., Ltd., J., and JEWSBURY, J. June 18, 1938, No. 18166. [Class 83 (iii)] A radial arm drilling-machine of the type in which the arm is carried by a sleeve a pivoted on the column d has interengaging surfaces b, c on the column and sleeve such that the pressure between the surfaces prevents rotation of the sleeve and arm. An abutment e on the column is engaged by a convex surface on a lever h having a concave surface to engage a second abutment g connected to the column by a bolt. The lever is pivoted on a spindle m adjustable by eccentric bearings and is operated to relieve the pressure between the surfaces b, c by an eccentric o operated by worm gearing. |
