Issued Patents 2002
Showing 1–4 of 4 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6450401 | Writing board with electronic calculator | Kashichi Hirota | 2002-09-17 |
| 6427928 | Straw with plug | Kashichi Hirota | 2002-08-06 |
| 6416329 | Writing device for practice in writing characters | Kashichi Hirota | 2002-07-09 |
| 6375019 | Straw with plug | Kashichi Hirota | 2002-04-23 |