Title:
Lifting apparatus for earth boring equipment
United States Patent 3157065


Inventors:
Gustav, Isenberg
Friedrich, Klapdohr
Application Number:
US6314560A
Publication Date:
11/17/1964
Filing Date:
10/17/1960
Assignee:
DEMAG AG
Primary Class:
Other Classes:
74/665L, 126/273R
International Classes:
E21B3/06
View Patent Images:
US Patent References:
Foreign References:
GB745922A1956-03-07
DE969891C1958-07-31
AT203435B1959-05-11