Ferrotec Corporation
24Patents
10Active
24Granted
41Portfolio score
Filing activity: Sep 23, 1985 → Mar 12, 2013 · 7 expiring within 5 years
Most-cited patents
| Patent | Title | Area | Cited by | Status |
|---|---|---|---|---|
| US6305694A | Ferrofluid sealing device | Mechanical Engineering; Lighting; Heating | 25 | Expired |
| US4706498A | Apparatus and method for measuring movement | Physics | 20 | Expired |
| US4862752A | D.C. excited capacitive shaft rotation transducer | Electricity | 19 | Expired |
| US7729504B2 | Ferrofluid centered voice coil speaker | Electricity | 17 | Active |
| US6056889A | Process for producing a magnetic fluid and composition therefor | Electricity | 16 | Expired |
| US7063802B2 | Composition and method of making an element-modified ferrofluid | Electricity | 13 | Expired |
| US5676877A | Process for producing a magnetic fluid and composition therefor | Electricity | 10 | Expired |
| US6804368B2 | Micro-speaker and method for assembling a micro-speaker | Emerging Cross-Sectional Technologies | 9 | Expired |
| US5876037A | Magnetic fluid sealing device | Mechanical Engineering; Lighting; Heating | 6 | Expired |
| US5879580A | Ferrofluid having improved oxidation resistance | Electricity | 5 | Expired |
| US5730893A | Magnetic colloids using acid terminated poly (12-hydroxystearic acid) dispersants | Electricity | 5 | Expired |
| US5656196A | Ferrofluid having improved oxidation resistance | Electricity | 4 | Expired |
| US6868167B2 | Audio speaker and method for assembling an audio speaker | Emerging Cross-Sectional Technologies | 2 | Expired |
| US7266214B2 | Audio speaker and method for assembling an audio speaker | Emerging Cross-Sectional Technologies | 2 | Expired |
| US7976612B2 | Droplet removing device and method in plasma generator | Electricity | 2 | Active |
| US8833299B2 | Divided annular rib type plasma processing apparatus | Electricity | 1 | Active |
| US7248714B2 | Micro-speaker and method for assembling a micro-speaker | Emerging Cross-Sectional Technologies | 1 | Expired |
| US9448262B2 | Current sensor having at least one cancel coil | Physics | 1 | Active |
| US9426875B2 | Method for producing plasma flow, method for plasma processing, apparatus for producing plasma, and apparatus for plasma processing | Electricity | 1 | Active |
| US8007176B2 | Dynamic pressure bearing and rotation machine employing same | Electricity | 0 | Active |
| US8999122B2 | Insulator interposed type plasma processing apparatus | Electricity | 0 | Active |
| US9627111B2 | Magnetic member and electronic component | Electricity | 0 | Active |
| US7823537B2 | Plasma generator | Electricity | 0 | Active |
| US8562800B2 | Plasma generating apparatus and plasma processing apparatus | Electricity | 0 | Active |
Source: USPTO / EPO open patent data. Counts and citation impact are objective bibliographic measures.