| # | Country | Total Patents | |
|---|---|---|---|
| #1 | United States | 19 | |
| #2 | Germany | 1 | |
| #3 | United Kingdom | 1 |
| # | Industry | |
|---|---|---|
| #1 | Civil engineering | |
| #2 | Machines | |
| #3 | Machine tools | |
| #4 | Engines, pumps and turbines |
| # | Technology | |
|---|---|---|
| #1 | Earth drilling | |
| #2 | Unspecified technologies | |
| #3 | Tools for connecting or disengaging | |
| #4 | Making forged metal products | |
| #5 | Pumps |
| # | Name | Total Patents |
|---|---|---|
| #1 | George Krell | 10 |
| #2 | Davis Marvin B | 8 |
| #3 | Warren Clarence G | 1 |
| Publication | Filing date | Title |
|---|---|---|
| US2211016A | Elevator | |
| US1753843A | Tool-dressing apparatus | |
| US1702350A | Pull-rod retainer | |
| US1702349A | Elevator | |
| US1726521A | Clamping spider | |
| US1693502A | Apparatus for gripping pipes, rods, or the like | |
| US1649451A | Pipe-elevating clamp | |
| US1642230A | Draw works | |
| US1647688A | Clamp | |
| US1693478A | Pipe clamp | |
| US1654866A | Pipe clamp | |
| US1669401A | Clamping device for oil-well pipes | |
| US1564001A | Pipe clamp | |
| US1552062A | Clamping device | |
| US1504355A | Casing elevator | |
| US1504354A | Well-tubing elevator | |
| US1499225A | Casing elevator | |
| US1530727A | Engine starter | |
| US1500459A | Casing elevator |