Robert C. Berfield
147Patents
26h-index
28Co-inventors
90Inventor score
Filing activity: Feb 5, 1980 → Mar 15, 2007
Most-cited inventions
| Patent | Title | Area | Cited by | Status |
|---|---|---|---|---|
| US4270668A | Buckle or latch for holding lid to container | Emerging Cross-Sectional Technologies | 72 | Expired |
| US4797072A | Portable electric blower | Human Necessities | 63 | Expired |
| US4435877A | Noise reducing means for vacuum cleaner | Human Necessities | 62 | Expired |
| US6107583A | Switch assembly having an enlarged actuation surface | Electricity | 59 | Expired |
| USD389962S | Combined wet and dry vacuum cleaner | General | 50 | Expired |
| US4880364A | Portable electric blower | Human Necessities | 47 | Expired |
| US4330899A | Noise reducing blower motor housing means for vacuum cleaner, or the like | Mechanical Engineering; Lighting; Heating | 47 | Expired |
| US4836753A | Portable electric blower | Emerging Cross-Sectional Technologies | 44 | Expired |
| US4501378A | Resilient detented lid latch | Emerging Cross-Sectional Technologies | 42 | Expired |
| US6440191B1 | Vacuum cleaner filter assembly | Emerging Cross-Sectional Technologies | 41 | Expired |
| USD358010S | Combined wet and dry vacuum cleaner | General | 41 | Expired |
| US5855634A | Filter retainer for a vacuum cleaner | Emerging Cross-Sectional Technologies | 41 | Expired |
| USD287171S | Motor housing for canister type electric vacuum cleaner | General | 40 | Expired |
| US4334337A | Compact wet-dry electric vacuum cleaner | Human Necessities | 36 | Expired |
| US4906265A | Filter and installation means for dry material filter for electric vacuum cleaner | Emerging Cross-Sectional Technologies | 34 | Expired |
| US4462137A | Electric vacuum cleaner | Human Necessities | 34 | Expired |
| USD395119S | Dolly | General | 33 | Expired |
| US4701969A | Rotary brush sweeper with easily separable debris pan | Human Necessities | 32 | Expired |
| US5555597A | Apparatus for converting a vacuum cleaning device into a liquid dispensing and suctioning system | Human Necessities | 29 | Expired |
| US5313686A | Tool caddy for attachment to container, particularly for a vacuum cleaner tank | Human Necessities | 29 | Expired |
| USD286336S | Tank for electric vacuum cleaner | General | 28 | Expired |
| US4709436A | Debris pan for rotary brush sweeper | Fixed Constructions | 28 | Expired |
| US6009596A | Self-evacuating vacuum cleaner | Human Necessities | 28 | Expired |
| US4475265A | Shoe attachment for wet/dry electric vacuum cleaner | Human Necessities | 27 | Expired |
| US5920955A | Self-evacuating vacuum cleaner | Human Necessities | 27 | Expired |
Source: USPTO / EPO open patent data. Inventor disambiguation is heuristic; counts are objective bibliographic measures.