| # | Country | Total Patents | |
|---|---|---|---|
| #1 | Australia | 4 | |
| #2 | EPO (European Patent Office) | 4 | |
| #3 | United States | 4 | |
| #4 | Brazil | 3 | |
| #5 | Canada | 2 | |
| #6 | China | 2 | |
| #7 | Germany | 2 | |
| #8 | India | 2 | |
| #9 | Argentina | 1 | |
| #10 | Belgium | 1 | |
| #11 | France | 1 | |
| #12 | United Kingdom | 1 | |
| #13 | Italy | 1 | |
| #14 | Japan | 1 | |
| #15 | Republic of Korea | 1 |
| # | Industry | |
|---|---|---|
| #1 | Chemical engineering | |
| #2 | Civil engineering | |
| #3 | Machines | |
| #4 | Mechanical elements |
| # | Technology | |
|---|---|---|
| #1 | Earth drilling | |
| #2 | Chemical or physical processes | |
| #3 | Separation | |
| #4 | Unspecified technologies | |
| #5 | Unspecified technologies | |
| #6 | Pipes |
| # | Name | Total Patents |
|---|---|---|
| #1 | Nagaoka Tadayoshi | 23 |
| #2 | Tadayoshi Nagaoka | 4 |
| Publication | Filing date | Title |
|---|---|---|
| US5069279A | Well structure having a screen element with wire supporting rods | |
| EP0228262A2 | Double cylinder screen | |
| CN1006481B | Cylindrical screen | |
| JPS61164612A | Powerless rotary type filter apparatus | |
| AU3375884A | Joint for tubular articles manufactured from different materials | |
| US4578248A | Distributor/collector assembly |