| # | Country | Total Patents | |
|---|---|---|---|
| #1 | United States | 11 | |
| #2 | Canada | 1 |
| # | Industry | |
|---|---|---|
| #1 | Mechanical elements | |
| #2 | Measurement | |
| #3 | Engines, pumps and turbines | |
| #4 | Chemical engineering |
| # | Technology | |
|---|---|---|
| #1 | Venting or aerating devices | |
| #2 | Special measuring | |
| #3 | Analysing materials | |
| #4 | Pumps | |
| #5 | Measuring volume | |
| #6 | Chemical or physical laboratory devices | |
| #7 | Cyclically operating valves |
| # | Name | Total Patents |
|---|---|---|
| #1 | Welker Robert H | 12 |
| Publication | Filing date | Title |
|---|---|---|
| US4830334A | Resilient plug construction for a flow regulator incorporating stress limiting means | |
| US4346611A | Insertion regulator for pressurized pipelines | |
| US4354661A | Constant velocity diffuser | |
| US4351510A | Flow regulator assembly | |
| US4315616A | Dump valve | |
| US4224629A | Disc chart paper with reinforced separating edge | |
| US4172670A | Liquid sample collection apparatus | |
| US4177676A | Sensor positioning apparatus | |
| US3945770A | High pressure pump | |
| US3904176A | Pivot valve | |
| US2917269A | Flow regulator |