Darrell C. Symonds
7Patents
3h-index
2Co-inventors
43Inventor score
Filing activity: Nov 7, 1979 → Apr 19, 1993
Most-cited inventions
| Patent | Title | Area | Cited by | Status |
|---|---|---|---|---|
| USD267320S | Blade plough | General | 17 | Expired |
| US4796939A | Lifting means | Performing Operations; Transporting | 13 | Expired |
| US5437336A | Method and apparatus for creating an advantageous growing zone in a soilbed having a topsoil stratum and a hardpan stratum | Human Necessities | 9 | Expired |
| US4974681A | Method for fracturing sub-surface hardpan by drawing a particularly-angled tine therethrough | Human Necessities | 3 | Expired |
| US4815545A | Subsoil blade ploughs | Human Necessities | 2 | Expired |
| US4800713A | Rotary rakes | Human Necessities | 1 | Expired |
| US4821499A | Rotary rakes | Human Necessities | 0 | Expired |
Source: USPTO / EPO open patent data. Inventor disambiguation is heuristic; counts are objective bibliographic measures.