Inventor · Chiba, JP

Hajime Oyama

118Patents
21h-index
103Co-inventors
93Inventor score

Filing activity: Nov 17, 1976 → May 18, 2022

Most-cited inventions

PatentTitleAreaCited byStatus
US6505014B2 Image forming apparatus and an image forming process unit Physics 72 Expired
US5805965A Developing device for an image forming apparatus having developer distribution features Physics 58 Expired
US5659860A Developing device for an image forming apparatus and toner cartridge Physics 56 Expired
US5771426A Developing device using a toner and carrier mixture Physics 45 Expired
US6611672B2 Image forming apparatus, monocolor image forming apparatus, toner recycling apparatus and intermediate transfer member Physics 44 Expired
US6721516B2 Image forming apparatus Physics 43 Expired
US4194830A Development apparatus Physics 41 Expired
US5822664A Developing machine which uses a developing agent including a toner and magnetic particles Physics 38 Expired
US6658227B2 Development method apparatus, image formation and process cartridge for suppressing variation in toner charge Physics 33 Expired
US5198861A Image density control method for an image forming apparatus for reducing background contamination of a photoconductive drum Physics 33 Expired
US5083160A Image density control method and color image forming apparatus Physics 33 Expired
US7171145B2 Developing device and process cartridge for an image forming apparatus Physics 32 Expired
US5758241A Developing device for an image forming apparatus Physics 32 Expired
US5864733A Developing device for image forming apparatus Physics 31 Expired
US4382420A Development apparatus Physics 28 Expired
US5182600A Toner end detecting method for an electrophotographic copier Physics 27 Expired
US4286543A Apparatus for developing electrostatic image Physics 25 Expired
US5771429A Developing device capable of automatic toner content control Physics 25 Expired
US7890231B2 Lane keeping assistance equipment for automotive vehicles Performing Operations; Transporting 23 Active
US4406536A Developing device Physics 22 Expired
US5450177A Image forming apparatus having a toner concentration control capability with a toner concentration sensor disposed in a developing unit Physics 22 Expired
US4165393A Magnetic brush developing process for electrostatic images Physics 21 Expired
US7035575B2 Developing device, image forming apparatus, and process cartridge Physics 19 Expired
US6686845B2 Driver's arousal level estimating apparatus for vehicle and method of estimating arousal level Performing Operations; Transporting 17 Expired
US7084773B2 Wakefulness estimating apparatus and method Human Necessities 17 Expired

Source: USPTO / EPO open patent data. Inventor disambiguation is heuristic; counts are objective bibliographic measures.