| # | Country | Total Patents | |
|---|---|---|---|
| #1 | France | 11 | |
| #2 | United Kingdom | 1 | |
| #3 | United States | 1 |
| # | Industry | |
|---|---|---|
| #1 | Transport | |
| #2 | Engines, pumps and turbines | |
| #3 | Measurement | |
| #4 | Mechanical elements | |
| #5 | Electrical machinery and energy |
| # | Technology | |
|---|---|---|
| #1 | Aeroplanes | |
| #2 | Non-positive-displacement pumps | |
| #3 | Mechanically-driven clocks | |
| #4 | Marine propulsion | |
| #5 | Gearing | |
| #6 | Servomotors | |
| #7 | Measuring force, work and fluid pressure | |
| #8 | Dynamo-electric machines |
| # | Name | Total Patents |
|---|---|---|
| #1 | Dreptin Paul-Maurice | 6 |
| #2 | Dreptin Paul | 2 |
| #3 | Paul Dreptin | 1 |
| Publication | Filing date | Title |
|---|---|---|
| US2954829A | Variable pitch propeller for airplanes or other flying machines | |
| GB756134A | An improved variable-pitch propeller for airplanes or other flying machines |