Inventor · Calgary, AB, CA

Clarence W. Johnson

22Patents
12h-index
2Co-inventors
71Inventor score

Filing activity: Mar 8, 1979 → Feb 27, 2018

Most-cited inventions

PatentTitleAreaCited byStatus
US8302796B1 Utility box anti-theft lock brackets Electricity 48 Active
US5224898A Cushion connector Fixed Constructions 31 Expired
US6015134A Pneumatic actuator assembly Emerging Cross-Sectional Technologies 28 Expired
US5464040A Safety valve actuator Emerging Cross-Sectional Technologies 17 Expired
US4844466A Block puzzle Human Necessities 15 Expired
US6116268A Wellhead safety valve control system Emerging Cross-Sectional Technologies 13 Expired
US4593914A Wellhead sealing system Emerging Cross-Sectional Technologies 13 Expired
US4494778A Casing hanger Fixed Constructions 13 Expired
US4759738A Floating cushion sub Fixed Constructions 12 Expired
US4703812A Mobile drilling apparatus Fixed Constructions 12 Expired
US5971353A Dump/stop valve for surface controlled subsurface safety valve Emerging Cross-Sectional Technologies 12 Expired
US6412510B1 Wellhead safety valve control system Emerging Cross-Sectional Technologies 12 Expired
US4784392A Block puzzle Human Necessities 11 Expired
US5341837A Two line pilot valve Emerging Cross-Sectional Technologies 9 Expired
US5791285A Automatic aquatic food and water delivery device Emerging Cross-Sectional Technologies 7 Expired
US5291918A Safety valve actuator assembly Emerging Cross-Sectional Technologies 7 Expired
US5070900A Safety valve actuator assembly Emerging Cross-Sectional Technologies 7 Expired
US4268988A """2"" in ""1"" Bobber super and regular" Human Necessities 6 Expired
US4287776A Force transducer Physics 4 Expired
US5590685A High-low indicator Emerging Cross-Sectional Technologies 3 Expired
US10716297B2 Automatic fish feeder Emerging Cross-Sectional Technologies 1 Active
US6053711A Pump for pressurizing control system Mechanical Engineering; Lighting; Heating 1 Expired

Source: USPTO / EPO open patent data. Inventor disambiguation is heuristic; counts are objective bibliographic measures.