John D. Barr
44Patents
24h-index
19Co-inventors
82Inventor score
Filing activity: Jan 9, 1981 → Apr 13, 2007
Most-cited inventions
| Patent | Title | Area | Cited by | Status |
|---|---|---|---|---|
| US5265682A | Steerable rotary drilling systems | Fixed Constructions | 276 | Expired |
| US5553678A | Modulated bias units for steerable rotary drilling systems | Fixed Constructions | 262 | Expired |
| US5706905A | Steerable rotary drilling systems | Fixed Constructions | 257 | Expired |
| US5520255A | Modulated bias unit for rotary drilling | Fixed Constructions | 220 | Expired |
| US5803185A | Steerable rotary drilling systems and method of operating such systems | Fixed Constructions | 183 | Expired |
| US6089332A | Steerable rotary drilling systems | Fixed Constructions | 181 | Expired |
| US5685379A | Method of operating a steerable rotary drilling system | Fixed Constructions | 161 | Expired |
| US5582259A | Modulated bias unit for rotary drilling | Fixed Constructions | 158 | Expired |
| US5695015A | System and method of controlling rotation of a downhole instrument package | Fixed Constructions | 145 | Expired |
| US4593777A | Drag bit and cutters | Fixed Constructions | 114 | Expired |
| US4694919A | Rotary drill bits with nozzle former and method of manufacturing | Emerging Cross-Sectional Technologies | 88 | Expired |
| US5025874A | Cutting elements for rotary drill bits | Performing Operations; Transporting | 82 | Expired |
| US4780274A | Manufacture of rotary drill bits | Emerging Cross-Sectional Technologies | 77 | Expired |
| US4558753A | Drag bit and cutters | Fixed Constructions | 71 | Expired |
| US4679639A | Rotary drill bits and cutting elements for such bits | Fixed Constructions | 64 | Expired |
| US4804049A | Rotary drill bits | Performing Operations; Transporting | 43 | Expired |
| US4942933A | Relating to rotary drill bits | Fixed Constructions | 40 | Expired |
| US5165494A | Rotary drills bits | Fixed Constructions | 40 | Expired |
| US4505342A | Drill bit | Fixed Constructions | 40 | Expired |
| US4660659A | Drag type drill bit | Fixed Constructions | 37 | Expired |
| US4733735A | Rotary drill bits | Fixed Constructions | 32 | Expired |
| US4382477A | Rotary drill bits | Emerging Cross-Sectional Technologies | 31 | Expired |
| US5099934A | Rotary drill bits | Fixed Constructions | 29 | Expired |
| US4640375A | Drill bit and cutter therefor | Fixed Constructions | 28 | Expired |
| US4577706A | Rotary drill bits | Fixed Constructions | 24 | Expired |
Source: USPTO / EPO open patent data. Inventor disambiguation is heuristic; counts are objective bibliographic measures.