Issued Patents All Time
Showing 1–4 of 4 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| RE33872 | Magnetic-tape cassette with a latching cover plate | Karel G. M. Koken, John C. J. Olierook, Cornelis M. Beyersbergen | 1992-04-07 |
| 4672598 | Disc loading mechanism | Karel G. M. Koken | 1987-06-09 |
| 4634020 | Cassette with a latching pivoted cover | Cornelis M. Beyersbergen van Henegouwen, Karel G. M. Koken, John C. J. Olierook | 1987-01-06 |
| 4576345 | Magnetic-tape cassette with a latching cover plate | Karel G. M. Koken, John C. J. Olierook, Cornelis M. Beyersbergen van Henegouwen | 1986-03-18 |