David E. Johnston
33Patents
14h-index
14Co-inventors
78Inventor score
Filing activity: Aug 2, 1979 → Jun 11, 2009
Most-cited inventions
| Patent | Title | Area | Cited by | Status |
|---|---|---|---|---|
| US5921555A | Uni-directional seal for use on a shaft | Mechanical Engineering; Lighting; Heating | 48 | Expired |
| US5791658A | Seal design with bi-directional pumping | Mechanical Engineering; Lighting; Heating | 42 | Expired |
| US4855583A | Structure and method of making combination proximity/insertion identification cards | Physics | 40 | Expired |
| US5427387A | Radial shaft sealing ring | Mechanical Engineering; Lighting; Heating | 36 | Expired |
| US6428013B1 | Reverse seal | Mechanical Engineering; Lighting; Heating | 36 | Expired |
| US5190299A | Radially undulating shaft seal | Mechanical Engineering; Lighting; Heating | 34 | Expired |
| US7640069B1 | Editing audio directly in frequency space | Electricity | 33 | Active |
| US6729624B1 | Radial shaft seal | Mechanical Engineering; Lighting; Heating | 32 | Expired |
| US5348312A | Cassette seal | Mechanical Engineering; Lighting; Heating | 30 | Expired |
| US6409177B1 | Rotary shaft seal | Mechanical Engineering; Lighting; Heating | 30 | Expired |
| US4296114A | 3,4-Dihydro-3-oxopyrido[2,3-b]-pyrazines, compositions and use thereof | Chemistry; Metallurgy | 27 | Expired |
| US8027743B1 | Adaptive noise reduction | Physics | 25 | Active |
| US7548791B1 | Graphically displaying audio pan or phase information | Physics | 24 | Active |
| US4348031A | Rotary fluid seals with floating sealing rings | Mechanical Engineering; Lighting; Heating | 24 | Expired |
| US6073933A | Load bearing washer and dirt excluder | Mechanical Engineering; Lighting; Heating | 14 | Expired |
| US4815749A | Shaft and like oil seals | Mechanical Engineering; Lighting; Heating | 13 | Expired |
| US4519616A | Shaft seal | Mechanical Engineering; Lighting; Heating | 13 | Expired |
| US7899565B1 | Graphically displaying audio pan or phase information | Physics | 9 | Active |
| US6178882A | Shearing compactor pump | Emerging Cross-Sectional Technologies | 8 | Expired |
| US5123661A | Fluid sealing structure | Mechanical Engineering; Lighting; Heating | 7 | Expired |
| US4462600A | Rotary fluid seals | Mechanical Engineering; Lighting; Heating | 7 | Expired |
| US5380660A | Method of treating serum or serum-containing medium to inactivate an inhibitor of hepatocyte differentiation | Chemistry; Metallurgy | 6 | Expired |
| US4799693A | Face seals with liquid pulsation pumping feature | Mechanical Engineering; Lighting; Heating | 5 | Expired |
| US8194884B1 | Aligning time variable multichannel audio | Electricity | 4 | Active |
| US7610110B1 | Graphically displaying stereo phase information | Electricity | 4 | Active |
Source: USPTO / EPO open patent data. Inventor disambiguation is heuristic; counts are objective bibliographic measures.