| # | Country | Total Patents | |
|---|---|---|---|
| #1 | United States | 9 | |
| #2 | Canada | 2 |
| # | Industry | |
|---|---|---|
| #1 | Engines, pumps and turbines | |
| #2 | Machines | |
| #3 | Mechanical elements | |
| #4 | Machine tools |
| # | Technology | |
|---|---|---|
| #1 | Cyclically operating valves | |
| #2 | Unspecified technologies | |
| #3 | Venting or aerating devices | |
| #4 | Machines | |
| #5 | Pumps | |
| #6 | Servomotors | |
| #7 | Grinding or polishing devices |
| # | Name | Total Patents |
|---|---|---|
| #1 | Prescott Charles F | 11 |
| #2 | Stafford Hal R | 2 |
| Publication | Filing date | Title |
|---|---|---|
| US1953541A | Distribution valve for fluid pressure engines | |
| US1634339A | Valve | |
| US1404646A | Throttle-valve operation | |
| US1340405A | Steam-engine valve-gear | |
| CA194637A | Operating valve for compound engines | |
| US1279433A | Operating-valve for compound engines. | |
| US973137A | Valve-gear for engines. | |
| US922036A | Engine valve-gear. | |
| US1019700A | Pump. | |
| US909665A | Engine valve-gear. | |
| CA284357A | Valve |