| # | Country | Total Patents | |
|---|---|---|---|
| #1 | Germany | 3 | |
| #2 | United Kingdom | 3 | |
| #3 | France | 2 | |
| #4 | Hong Kong | 2 | |
| #5 | Italy | 2 | |
| #6 | United States | 2 |
| # | Industry | |
|---|---|---|
| #1 | Mechanical elements | |
| #2 | Machine tools | |
| #3 | Machines |
| # | Technology | |
|---|---|---|
| #1 | Nails | |
| #2 | Tools for connecting or disengaging | |
| #3 | Unspecified technologies |
| # | Name | Total Patents |
|---|---|---|
| #1 | Yamamoto Keiichi | 6 |
| #2 | Yamamoto Kozo | 6 |
| Publication | Filing date | Title |
|---|---|---|
| US4006660A | Fastener element | |
| GB1491515A | Screw-threaded fastener | |
| GB1458089A | Fastener driver | |
| GB1458090A | Fastener element | |
| US3908489A | Fastener driver |