| # | Country | Total Patents | |
|---|---|---|---|
| #1 | United States | 15 | |
| #2 | Canada | 1 | |
| #3 | Germany | 1 | |
| #4 | France | 1 | |
| #5 | United Kingdom | 1 |
| # | Industry | |
|---|---|---|
| #1 | Transport | |
| #2 | Machines | |
| #3 | Machine tools | |
| #4 | Engines, pumps and turbines | |
| #5 | Environmental technology |
| # | Technology | |
|---|---|---|
| #1 | Aeroplanes | |
| #2 | Unspecified technologies | |
| #3 | Parachutes | |
| #4 | Punching metal | |
| #5 | Steam turbines | |
| #6 | Reduction of greenhouse gas emissions | |
| #7 | Unspecified technologies | |
| #8 | Non-positive-displacement pumps | |
| #9 | Wind motors | |
| #10 | Wood working |
| # | Name | Total Patents |
|---|---|---|
| #1 | Spencer Heath | 10 |
| #2 | William Stelzer | 3 |
| #3 | Semmes Harry H | 1 |
| #4 | Havill Clinton H | 1 |
| #5 | Heath Spencer | 1 |
| Publication | Filing date | Title |
|---|---|---|
| US1869478A | Method of forming a propeller | |
| US2012389A | Method of making propellers | |
| GB352239A | Improvements in variable pitch airscrews | |
| US2127687A | Propeller | |
| US1972654A | Impeller | |
| US1857909A | Propeller | |
| US1817952A | Propelling device for aircraft and the like | |
| US1875598A | Propeller | |
| US1843886A | Propeller | |
| US1904733A | Propeller | |
| US1838674A | Airscrew | |
| US1875597A | Propeller | |
| US1821450A | Propelling device for aircraft and the like | |
| US1919588A | Blade for windmill impellers | |
| US1899650A | Propeller | |
| US1802648A | Propeller | |
| CA332626A | Propeller |