| # | Country | Total Patents | |
|---|---|---|---|
| #1 | United States | 12 | |
| #2 | Switzerland | 1 |
| # | Industry | |
|---|---|---|
| #1 | Machines | |
| #2 | Mechanical elements | |
| #3 | Engines, pumps and turbines | |
| #4 | Thermal processes | |
| #5 | Measurement | |
| #6 | Chemical engineering |
| # | Technology | |
|---|---|---|
| #1 | Unspecified technologies | |
| #2 | Venting or aerating devices | |
| #3 | Cooling of machines | |
| #4 | Preheating for stem generation | |
| #5 | Measuring volume | |
| #6 | Steam turbines | |
| #7 | Cyclically operating valves | |
| #8 | Separation |
| # | Name | Total Patents |
|---|---|---|
| #1 | Ludeman Oscar H | 12 |
| #2 | Oscar H Ludeman | 1 |
| #3 | Ludeman Edwin H | 1 |
| Publication | Filing date | Title |
|---|---|---|
| US2765142A | Valves | |
| US2637520A | Valve | |
| US2698157A | Alternate manual and automatically operated valve | |
| US2660986A | Motor having hydraulically operated valve | |
| US2360612A | Valve | |
| US2307628A | Valve mechanism | |
| US2313448A | Valve | |
| US2215819A | Boiler feed system | |
| US1544916A | Boiler-feed-water system | |
| US1613233A | Separator | |
| US1462887A | Temperature alarm | |
| US1390532A | Heat and low-water indicator |