Inventor · disambiguated record
Seiji Oka
Also filed as: OKA SEIJI
57 granted patents·8 pending applications·1,087 citations·filing 1984–2023
99Inventor score
Files withMITSUBISHI ELECTRIC CORP22RICOH KK18OKA SEIJI11DAIKIN IND LTD5OMRON TATEISI ELECTRONICS CO3
Top patents by PatentIndex Score
65 records- 0198US5109254ADeveloping apparatusRICOH KK·Filed 1990·Granted Apr 28, 1992·101 cites·22 claims
- 0296US5416568ADeveloping unit for an image forming apparatusRICOH KK·Filed 1993·Granted May 16, 1995·67 cites·25 claims
- 0396US5235384AImage forming apparatus with replaceable process unitsRICOH KK·Filed 1990·Granted Aug 10, 1993·72 cites·11 claims
- 0495US5805965ADeveloping device for an image forming apparatus having developer distribution featuresRICOH KK·Filed 1996·Granted Sep 8, 1998·83 cites·41 claims
- 0595US4650070AToner cartridgeRICOH KK·Filed 1984·Granted Mar 17, 1987·47 cites·10 claims
- 0694US5659860ADeveloping device for an image forming apparatus and toner cartridgeRICOH KK·Filed 1995·Granted Aug 19, 1997·84 cites·20 claims
- 0793US5983059ARecyclable toner container for an image forming apparatusRICOH KK·Filed 1997·Granted Nov 9, 1999·66 cites·3 claims
- 0893US5771426ADeveloping device using a toner and carrier mixtureRICOH KK·Filed 1996·Granted Jun 23, 1998·67 cites·40 claims
- 0992US4800411AMagnetic brush development device for electrostatic latent imagesRICOH KK·Filed 1987·Granted Jan 24, 1989·42 cites·7 claims
- 1091US8502385B2Power semiconductor deviceOKA SEIJI·Filed 2011·Granted Aug 6, 2013·14 cites·10 claims
- 1191US5758241ADeveloping device for an image forming apparatusRICOH KK·Filed 1996·Granted May 26, 1998·56 cites·25 claims
- 1290US5822664ADeveloping machine which uses a developing agent including a toner and magnetic particlesRICOH KK·Filed 1995·Granted Oct 13, 1998·51 cites·12 claims
- 1389US4799608AToner cartridgeRICOH KK·Filed 1987·Granted Jan 24, 1989·33 cites·12 claims
- 1488US8436459B2Power semiconductor moduleOKA SEIJI·Filed 2009·Granted May 7, 2013·18 cites·7 claims
- 1587US5771429ADeveloping device capable of automatic toner content controlRICOH KK·Filed 1996·Granted Jun 23, 1998·42 cites·30 claims
- 1687US4969557AToner cartridgeRICOH KK·Filed 1985·Granted Nov 13, 1990·30 cites·17 claims
- 1783US8304882B2Power semiconductor deviceOKA SEIJI·Filed 2010·Granted Nov 6, 2012·6 cites·15 claims
- 1882US5255059AImage forming apparatusRICOH KK·Filed 1992·Granted Oct 19, 1993·27 cites·6 claims
- 1981US8575745B2Power semiconductor device, printed wiring board, and mechanism for connecting the power semiconductor device and the printed wiring boardOKA SEIJI·Filed 2011·Granted Nov 5, 2013·5 cites·8 claims
- 2081US8299601B2Power semiconductor module and manufacturing method thereofOKA SEIJI·Filed 2009·Granted Oct 30, 2012·10 cites·3 claims
- 2180US10508849B2Air conditioner with outdoor temperature sensing correlated to outdoor fan controlDAIKIN IND LTD·Filed 2018·Granted Dec 17, 2019·2 cites·6 claims
- 2279US8258618B2Power semiconductor moduleOBIRAKI YOSHIKO·Filed 2009·Granted Sep 4, 2012·10 cites·11 claims
- 2375US8741695B2Semiconductor device and method of manufacturing the sameOKA SEIJI·Filed 2012·Granted Jun 3, 2014·3 cites·5 claims
- 2474US8319333B2Power semiconductor moduleOKA SEIJI·Filed 2009·Granted Nov 27, 2012·6 cites·9 claims
- 2574US8253236B2Power semiconductor deviceOI TAKESHI·Filed 2011·Granted Aug 28, 2012·4 cites·5 claims
- 2673US7849706B2Indoor unit of an air conditionerDAIKIN IND LTD·Filed 2005·Granted Dec 14, 2010·6 cites·15 claims
- 2770US11835245B2Air conditioning system, and indoor unit of sameDAIKIN IND LTD·Filed 2023·Granted Dec 5, 2023·0 cites·10 claims
- 2868US8299603B2Power semiconductor deviceOKA SEIJI·Filed 2008·Granted Oct 30, 2012·4 cites·12 claims
- 2968US6664127B2Method of manufacturing multi-layer printed wiring boardMITSUBISHI ELECTRIC CORP·Filed 2001·Granted Dec 16, 2003·15 cites·5 claims
- 3066US7038143B2Wiring board, fabrication method of wiring board, and semiconductor deviceMITSUBISHI ELECTRIC CORP·Filed 2003·Granted May 2, 2006·13 cites·13 claims
- 3166US5077584AToner supply device for electrophotographic equipmentRICOH KK·Filed 1990·Granted Dec 31, 1991·15 cites·3 claims
- 3263US8952520B2Power semiconductor deviceOBIRAKI YOSHIKO·Filed 2009·Granted Feb 10, 2015·3 cites·7 claims
- 3361US9287201B2Semiconductor deviceSHIOTA HIROKI·Filed 2011·Granted Mar 15, 2016·2 cites·14 claims
- 3461US9196604B2Power semiconductor module having pattern laminated regionMITSUBISHI ELECTRIC CORP·Filed 2013·Granted Nov 24, 2015·1 cites·9 claims
- 3561US8994165B2Power semiconductor deviceOI TAKESHI·Filed 2009·Granted Mar 31, 2015·2 cites·7 claims
- 3661US6451710B1Method of manufacturing multi-layer printed wiring boardMITSUBISHI ELECTRIC CORP·Filed 2001·Granted Sep 17, 2002·10 cites·8 claims
- 3760US11846436B2Floor-standing air conditionerDAIKIN IND LTD·Filed 2023·Granted Dec 19, 2023·0 cites·7 claims
- 3858US8610261B2Power semiconductor deviceOKA SEIJI·Filed 2009·Granted Dec 17, 2013·1 cites·8 claims
- 3955US12352674B2Test method and method for manufacturing semiconductor deviceMITSUBISHI ELECTRIC CORP·Filed 2022·Granted Jul 8, 2025·0 cites·10 claims
- 4055US4591623AThermosetting resin compositionMITSUBISHI ELECTRIC CORP·Filed 1985·Granted May 27, 1986·10 cites·3 claims
- 4154US6629362B2Method of manufacturing a circuit print boardMITSUBISHI ELECTRIC CORP·Filed 2001·Granted Oct 7, 2003·6 cites·8 claims
- 4254US6108511AToner collecting and reusing device for use in an image forming apparatus and a method thereofRICOH KK·Filed 1999·Granted Aug 22, 2000·11 cites·34 claims
- 4354US5555469AImage forming apparatus having toner recycling device with electrostatic conveyorRICOH KK·Filed 1994·Granted Sep 10, 1996·10 cites·8 claims
- 4453US7630794B2Isolated operation detecting method, control apparatus for detecting isolated operation for distributed power supplyOMRON TATEISI ELECTRONICS CO·Filed 2007·Granted Dec 8, 2009·2 cites·15 claims
- 4551US6807072B2Electric power conversion device with push-pull circuitryOMRON TATEISI ELECTRONICS CO·Filed 2003·Granted Oct 19, 2004·10 cites·5 claims
- 4649US8313986B2Method of manufacturing power semiconductor deviceOKA SEIJI·Filed 2012·Granted Nov 20, 2012·0 cites·22 claims
- 4749US2024274557A1Semiconductor device and power converting deviceMITSUBISHI ELECTRIC CORP·Filed 2021·Application pending·0 cites
- 4848US4882389AElectrical insulating resinMITSUBISHI ELECTRIC CORP·Filed 1987·Granted Nov 21, 1989·7 cites·5 claims
- 4948US2010134979A1Power semiconductor apparatusMITSUBISHI ELECTRIC CORP·Filed 2009·Application pending·0 cites
- 5046US2023197668A1Power semiconductor module and power conversion apparatusMITSUBISHI ELECTRIC CORP·Filed 2020·Application pending·0 cites
Showing the top 50 of 65 patent records by PatentIndex Score.
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Identity basis: PatentsView inventor disambiguation (2025Q4-odp release). How scoring works →