IP Library › Granted Patent US 4,420,188
Granted Patent Utility
US 4,420,188 · App. 06/325,101

Double shield tunnel boring machine

Inventors: Richard J. Robbins, David T. Cass
Patented Case View Patent ↗
Granted: Dec 13, 1983 Filed: Nov 27, 1981
Inventors
Richard J. Robbins
David T. Cass
Assignee (at issue)
Robbins, Inc.

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Quick Facts
Patent No.
US 4,420,188
App. No.
06/325,101
Filed
1981-11-27
Granted
1983-12-13
Kind
A