| # | Country | Total Patents | |
|---|---|---|---|
| #1 | United States | 11 | |
| #2 | France | 2 | |
| #3 | Germany | 1 | |
| #4 | United Kingdom | 1 |
| # | Industry | |
|---|---|---|
| #1 | Measurement | |
| #2 | Machines | |
| #3 | Optics | |
| #4 | Machine tools |
| # | Technology | |
|---|---|---|
| #1 | Measuring length, angles and areas | |
| #2 | Unspecified technologies | |
| #3 | Optical systems | |
| #4 | Turning | |
| #5 | Unspecified technologies | |
| #6 | Thread cutting |
| # | Name | Total Patents |
|---|---|---|
| #1 | James Hartness | 11 |
| #2 | Hartness James | 2 |
| #3 | Porter Russell W | 1 |
| Publication | Filing date | Title |
|---|---|---|
| GB328349A | Means for comparing the outlines of screws with standard outline charts by optical methods | |
| US1874517A | Screw thread gauging | |
| US1922849A | Gauging of screw threads | |
| US1905705A | Screw thread gauge | |
| US1714780A | Gauge for screw threads | |
| US1745537A | Cradle carriage for comparators | |
| US1829797A | Thread gauging | |
| US1703933A | Optical comparator | |
| US1704741A | Automatic die | |
| US1480390A | Apparatus for inspecting and gauging screw threads | |
| US1377069A | Mechanism for gaging screw-threads | |
| US1377068A | Process of inspecting and gaging screw-threads |