Issued Patents 1989
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4884910 | Mechanical pencil | Hidehei Kageyama, Yoichi Nakazato | 1989-12-05 |
| 4872776 | Lead chuck of mechanical pencil | Hidehei Kageyama, Yoichi Nakazato | 1989-10-10 |
| 4836703 | Lead cartridge opening and closing unit | Hidehei Kageyama, Saburo Kobayashi | 1989-06-06 |