Title:
Drilling apparatus
United States Patent 2781185


Inventors:
Davis, Robbins
Application Number:
US43399154A
Publication Date:
02/12/1957
Filing Date:
06/02/1954
Assignee:
Davis, Robbins
Primary Class:
Other Classes:
173/147, 175/85, 175/209, 175/220, 175/323, 211/70.4, 414/22.66
International Classes:
E21B19/084; E21B19/14; E21B19/20; E21B21/015
View Patent Images:
US Patent References:
2660403Posthole forming machine1953-11-24
2594098Drilling apparatus1952-04-22
2557049Power-driven posthole digger1951-06-12
2527255Well rig1950-10-24
2215928Drilling apparatus1940-09-24
2202446Pipe grip1940-05-28
2145939Dust hood1939-02-07
2114305Chuck mechanism1938-04-19
1242305N/A1917-10-09
1065409N/A1913-06-24