| # | Country | Total Patents | |
|---|---|---|---|
| #1 | United Kingdom | 3 | |
| #2 | Germany | 2 | |
| #3 | France | 2 | |
| #4 | Netherlands | 2 | |
| #5 | Belgium | 1 | |
| #6 | Norway | 1 | |
| #7 | United States | 1 |
| # | Industry | |
|---|---|---|
| #1 | Mechanical elements |
| # | Technology | |
|---|---|---|
| #1 | Venting or aerating devices | |
| #2 | Pipe-line systems |
| # | Name | Total Patents |
|---|---|---|
| #1 | Cupedo Douwe Janse | 2 |
| #2 | Cupedo Douwe J | 1 |
| #3 | Cupedo D J Jr | 1 |
| Publication | Filing date | Title |
|---|---|---|
| DE2748201A1 | THROTTLE VALVE | |
| NL7711817A | Adjustable type butterfly valve - has transverse pin working in inclined slot in actuating rod head and vertical grooves | |
| GB1316885A | Fluid-operated actuating mechanisms | |
| GB1329436A | Safety devices responsive to leakage in piping |