John C. Dunfield
46Patents
22h-index
18Co-inventors
78Inventor score
Filing activity: Jun 21, 1990 → Feb 4, 2000
Most-cited inventions
| Patent | Title | Area | Cited by | Status |
|---|---|---|---|---|
| US5028852A | Position detection for a brushless DC motor without hall effect devices using a time differential method | Electricity | 113 | Expired |
| US5254914A | Position detection for a brushless DC motor without Hall effect devices using a mutual inductance detection method | Electricity | 113 | Expired |
| US5694268A | Spindle motor having overmolded stator | Physics | 68 | Expired |
| US5841252A | Detection of starting motor position in a brushless DC motor | Electricity | 53 | Expired |
| US5569990A | Detection of starting motor position in a brushless DC motor | Electricity | 52 | Expired |
| US5579188A | Ironless spindle motor for disc drive | Electricity | 50 | Expired |
| US6538836B1 | Microactuator for fine positioning in a disc drive | Physics | 48 | Expired |
| US5619083A | Passive magnetic bearings for a spindle motor | Mechanical Engineering; Lighting; Heating | 47 | Expired |
| US5598048A | Integrated passive magnetic bearing system and spindle magnet for use in an axial magnet spindle motor | Electricity | 44 | Expired |
| US5587617A | Integrated passive magnetic bearing system and spindle magnet for use in an axial magnet spindle motor | Electricity | 40 | Expired |
| US5619389A | Stator isolation for spindle motor | Physics | 40 | Expired |
| US5729404A | Disc drive spindle motor with rotor isolation and controlled resistance electrical pathway from disc to ground | Electricity | 33 | Expired |
| US5548458A | Support flange having electrical contacts to provide electrical continuity upon spindle motor mounting to base | Electricity | 32 | Expired |
| US5541460A | Passive magnetic bearings for a spindle motor | Mechanical Engineering; Lighting; Heating | 29 | Expired |
| US5598071A | Method for starting and commutating a permanent-magnet direct current motor having a single phase winding | Electricity | 27 | Expired |
| US5949613A | Disk drive spindle motor assembly with stator having a resilient covering with a routing means, an attaching means and a connecting means to operatively connect stator to a base | Electricity | 27 | Expired |
| US5633568A | Method and apparatus for dynamic low voltage spindle motor operation | Physics | 27 | Expired |
| US5581424A | Magnetic crash stop and latch in a disc drive | Physics | 26 | Expired |
| US5956204A | Magnetic disc drive having magnetic particle trap for hydrodynamic bearing | Mechanical Engineering; Lighting; Heating | 24 | Expired |
| US5844748A | Disc drive spindle motor with controlled resistance pathway from disc to ground | Electricity | 23 | Expired |
| US5454724A | Floating electrical contact for spindle motor | Electricity | 23 | Expired |
| US5610463A | Passive magnetic bearings for a spindle motor | Mechanical Engineering; Lighting; Heating | 22 | Expired |
| US5850318A | Slotless spindle motor for disc drive | Electricity | 21 | Expired |
| US5561335A | Integrated passive magnetic bearing system and spindle permanent magnet for use in a spindle motor | Electricity | 19 | Expired |
| US5485331A | High resistivity bearing balls for spindle motor isolation | Electricity | 18 | Expired |
Source: USPTO / EPO open patent data. Inventor disambiguation is heuristic; counts are objective bibliographic measures.