Title:
ROCK DRILL
Document Type and Number:
Japanese Patent JPS54109001
Kind Code:
A
Abstract:
A rock drill system uses a high frequency, low energy per blow percussive drill device to drive a rock drill bit having a cylindrical sleeve and a breaking bar within the sleeve adjacent the cutting edge of the bit. The bit is operated without rotation and the low energy, high frequency enables operation without destroying the bit. A peening effect occurs around the outer circumference of the drilling end of the bit to create a slightly larger diameter than the diameter of the bit thereby enabling easy withdrawal from the hole.
Inventors:
HAAMAN RINDEBUUMU
Application Number:
JP13058678A
Publication Date:
August 27, 1979
Filing Date:
October 25, 1978
Export Citation:
Assignee:
INGERSOLL RAND CO
International Classes:
E21B1/38; E21B7/24; E21B10/00; E21B10/04; E21B10/36; E21B10/38; E21B10/40; (IPC1-7): E21B9/00; E21C13/00