| 摘要 |
441,152. Drilling - machines. DRINNAN, J., 490, Penistone Road, Sheffield. Aug. 31, 1934, Nos. 25127 and 28683. [Class 83 (iii)] In a portable rotary drilling-machine for operating on rock, coal, &c. an electric motor 3 is attached to a vertical column or support (not shown), about which it can be swung and carries studs 6 by which a casing 4 may be secured in any angular position about the axis of the motor shaft 2. Bearings 11 in the casing 4 support the shaft 2 which is provided with a pinion 10 engaging a bevel gear 9 supported by bearings 13 in a casing 8 attached to the casing 4. The boss 12 of the gear 9 has a polygonal bore which slidably receives the drill rod 14 carrying the drill 15. Feed may be applied to the drill rod by radial handles 19 screwed into a cap 16 rotatably supported on the drill rod by ball bearings 18, or alternatively a rack 21, Fig. 3, may be attached by a split bracket 22 to the casing 8, another bracket 23 being slidable on the rack by a hand-operated pinion 25. Open-sided slots 28 in the bracket 23 receive the handles 19 to impart feed to the drill on rotation of the pinion 25. In a modified construction, the drill rod 14 is dispensed with and the bore of the bevel gear boss 12 is circular to fit the drill 15, internal keys 30, Fig. 5, being provided to engage longitudinal slots in the drill. Enlargements 31 are also provided to allow the cutting points of the drill to pass through the boss. The boss 12 may be provided with interchangeable sleeves to receive either the drill rod 14 or the drill 15, or the drill may have a section similar to the rod 14. |
