| 摘要 |
IMPROVEMENTS IN DRILLING MACHINES A drilling machine for drilling holes in the ends of rails for a railway track to receive fishplate bolts, has a base 12 on which is provided a former 30 adapted to the profile of the rail 10. A clamping jaw 18 is connected by a clamping mechanism 16 for clamping the base 12 to the rail. An electric drill 20 is slidably supported on a column 14 on the base 12. An annular hole cutter 26 on the drill spindle 24 drills a hole through the web 40 of the rail 10. The former 30 accurately locates the drilling axis laterally with respect to the rail 10 and a respective end of the former 30 can be aligned with the rail end when clamping the machine to the rail in order that the drill axis will be accurately located longitudinally of the rail. |
