Inventor · Audubon, IA, US

David A. Hoffman

26Patents
6h-index
21Co-inventors
69Inventor score

Filing activity: Aug 1, 1977 → Apr 29, 2021

Most-cited inventions

PatentTitleAreaCited byStatus
US4281677A Supply valve for dual circuit systems Emerging Cross-Sectional Technologies 26 Expired
US6503438B2 Method and apparatus for balancing flowing conditions of laminar flowing materials Performing Operations; Transporting 21 Expired
US4677777A Price setting and display system for multiple unit merchandising machine Physics 15 Expired
US6484870B2 Dual belt conveyor system Performing Operations; Transporting 10 Expired
US4284184A Coin mechanism to merchandising machine interface Physics 8 Expired
US10273056B2 Fuel container system Performing Operations; Transporting 7 Active
US10113990B2 Microbial sensor system for the assessment of subsurface environments Emerging Cross-Sectional Technologies 5 Active
US9199172B2 System for software work events Emerging Cross-Sectional Technologies 3 Active
US9327198B2 Managing challenge events Emerging Cross-Sectional Technologies 2 Active
US7247278B2 Automated ground water monitoring and analysis system Physics 2 Expired
US9327197B2 Conducting challenge events Emerging Cross-Sectional Technologies 2 Active
US4139238A Vehicle braking systems Performing Operations; Transporting 2 Expired
US10656116B2 Microbial sensor system for the assessment of subsurface environments Emerging Cross-Sectional Technologies 1 Active
US10878143B2 Simulating selective participation of multiple events from a pool of qualified participants Physics 1 Active
US9612232B2 Static gel strength measurement apparatus and method Physics 1 Active
US11226306B2 Microbial sensor system for monitoring and imaging of an environment Physics 1 Active
US10265614B2 Managing challenge events Emerging Cross-Sectional Technologies 0 Active
US4466528A Apparatus for preventing circuit burn-out in multi-price merchandisers Physics 0 Expired
US11231385B2 Microbial sensor system for monitoring the environment and surfaces Physics 0 Active
US11635406B2 Microbial sensor system for the assessment of subsurface environments Emerging Cross-Sectional Technologies 0 Active
US10265613B2 Conducting challenge events Emerging Cross-Sectional Technologies 0 Active
US9792527B2 Automated slide comparator Physics 0 Active
US12281296B2 Electrochemical microbial sensor system and method of using same Physics 0 Active
US11933758B2 Methods and systems for monitoring microbial activity and communication in an environment Physics 0 Active
US9764223B2 Conducting challenge events Emerging Cross-Sectional Technologies 0 Active

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