Inventor · Yokohama, JP

Takayuki Maruta

25Patents
15h-index
43Co-inventors
77Inventor score

Filing activity: May 26, 1988 → Nov 14, 2005

Most-cited inventions

PatentTitleAreaCited byStatus
US4916547A Color image forming apparatus Physics 58 Expired
US5860038A Apparatus and method for detecting developing ability of an image forming apparatus Physics 56 Expired
US5270783A Image forming equipment having improved toner sensing Physics 46 Expired
US6160569A Image forming apparatus capable of changing process line speed Electricity 45 Expired
US5384628A Developing device for image forming equipment Physics 44 Expired
US5227842A Electrophotographic image forming apparatus which controls developer bias based on image irregularity Physics 39 Expired
US6055386A Apparatus and method for detecting developing ability of an image forming apparatus with varied LED continuous lighting time for image forming and process control modes Physics 38 Expired
US5671470A Color image forming device which changes developing bias when switching between developer units Physics 35 Expired
US6226481A Image forming apparatus with control over developing unit during an idle running of an intermediate image transfer body Physics 32 Expired
US5826146A Color image forming device which changes developing bias when switching between developer units Physics 31 Expired
US5298944A Testing image density to control toner concentration and dynamic range in a digital copier Physics 23 Expired
US6823149B2 Image forming apparatus with variable speed transferring and fixing devices Physics 23 Expired
US5424809A Image forming method and apparatus for the same Physics 19 Expired
US5835825A Color image forming device having a revolver developing unit Physics 17 Expired
US5724634A Image forming device in which developer roller speed is controlled in developer transfer to a photoconductive drum Physics 17 Expired
US5237369A Color image forming equipment responsive to changes in ambient conditions Physics 15 Expired
US5293198A Image forming apparatus for controlling the dynamic range of an image Physics 14 Expired
US7174124B2 Tandem color image forming apparatus with an image transfer belt and backup roller Physics 14 Expired
US5881334A Image forming apparatus and method for preventing wasted toner Physics 12 Expired
US6535707B2 Image forming system Physics 8 Expired
US7161712B2 Apparatus for forming images with proper gamma correction Electricity 4 Expired
US7474867B2 Magnetic carrier, two-component developer, development method, development device and image forming apparatus of electrophotography Physics 4 Expired
US7139512B2 Charging device, process cartridge and image forming apparatus Physics 4 Expired
USRE41934E1 Image forming system General 3 Expired
US7139517B2 Developing method for an image forming apparatus and developing device using the same Physics 1 Expired

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