Issued Patents All Time
Showing 1–7 of 7 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4584784 | Method and device for maintaining tools at a level | Cornelis J. Ravesteyn, Thomas J. Ruyter | 1986-04-29 |
| 4505214 | Dredged soil conveying vessel | Johannes C. Tjebbes | 1985-03-19 |
| 4449720 | Watertight seal between two concrete elements | Aloysius G. Roggekamp | 1984-05-22 |
| 4418484 | Method of dredging and dredging implement | Gerard W. H. Goedegebuure, Bartholomeus M. de Witt, Constantius H. M. Veltman | 1983-12-06 |
| 4374420 | Method of accurately dredging a desired profile contour | — | 1983-02-15 |
| 4250034 | Transport conduit | — | 1981-02-10 |
| 4204347 | Device for cutting loose hard ground material | — | 1980-05-27 |