Title:
Tunneling machine having suction exhaust means
United States Patent 3005627
Inventors:
William, Tinlin
Publication Date:
10/24/1961
Assignee:
William, Tinlin
Other Classes:
175/94, 175/102, 299/18, 299/62
International Classes:
E21D9/10; E21D9/13; E21D9/10; E21D9/12