Title:
Drive for earth boring tools
United States Patent 3009521


Inventors:
Failing, Jay C.
Application Number:
US74722058A
Publication Date:
11/21/1961
Filing Date:
07/08/1958
Assignee:
Failing, Jay C.
Primary Class:
Other Classes:
173/147, 173/167
International Classes:
E21B3/02; E21B19/15
View Patent Images:
US Patent References:
2781185Drilling apparatus1957-02-12
1368295Drive mechanism for drilling-machines1921-02-15
0459309N/A1891-09-08