Issued Patents All Time
Showing 1–5 of 5 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5890771 | Tunnel boring machine and method | — | 1999-04-06 |
| 5203614 | Tunneling machine having liquid balance low flow slurry system | Richard J. Robbins, Peter B. Dowden | 1993-04-20 |
| 5127711 | Hopper and hood combination for tunneling machine and tunneling machine having the same | — | 1992-07-07 |
| 4646853 | Shaft boring machine and method | David B. Sugden, Peter B. Dowden, Nicholas A. Hynd | 1987-03-03 |
| 4420188 | Double shield tunnel boring machine | Richard J. Robbins | 1983-12-13 |