FRUSTOCONICAL TUNNEL BORING HEAD HAVING RADIAL CONCAVE SCOOPS
United States Patent 3511539
US Patent References:
Excavating device
- - 1720195
Rotary type tunneling machine
- - 2837325
Tunnel-boring rotary head with adjustably mounted gauge cutters
- - 3232670
Excavating device
- - 1720195
Rotary type tunneling machine
- - 2837325
Tunnel-boring rotary head with adjustably mounted gauge cutters
- - 3232670
Inventors:
Schonfeld, Georg
Publication Date:
05/12/1970
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Export Citation:
Assignee:
Georg, Schonfeld
Primary Class:
Other Classes:
299/31, 299/110
International Classes:
E21D9/10; E21D9/11; E21D9/00; E21C29/02
Foreign References:
| GB934996A |