Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5046437 | Device in a button sewing machine for maintaining looseness in needle thread while preventing the thread from being pulled out of the sewing needle | Katsuo Hiratsuka, Koichi Nakayama, Masanori Ayuta | 1991-09-10 |
| 4967678 | Speed controller for controlling revolution speed of upper shaft of cycle sewing machine | Katsuo Hiratsuka, Masanori Ayuta, Koichi Nakayama | 1990-11-06 |