Inventor · disambiguated record
Keiji Wakahara
Also filed as: WAKAHARA KEIJI
41 granted patents·1 pending application·937 citations·filing 1991–2011
98Inventor score
Top patents by PatentIndex Score
42 records- 0198US6279390B1Thermostat malfunction detecting system for engine cooling systemDENSO CORP·Filed 1997·Granted Aug 28, 2001·73 cites·16 claims
- 0297US7316223B2Device for detecting malfunction in evaporated gas purging systemDENSO CORP·Filed 2006·Granted Jan 8, 2008·32 cites·5 claims
- 0396US6898927B2Emission control system with catalyst warm-up speeding controlDENSO CORP·Filed 2002·Granted May 31, 2005·99 cites·17 claims
- 0495US6679110B2Thermostat malfunction detecting system for engine cooling systemDENSO CORP·Filed 2002·Granted Jan 20, 2004·32 cites·16 claims
- 0594US7146851B2Diagnostic apparatus for variable valve control systemDENSO CORP·Filed 2005·Granted Dec 12, 2006·46 cites·31 claims
- 0694US6807851B2Leak-check apparatus of fuel-vapor-processing system, fuel-temperature estimation apparatus and fuel-temperature-sensor diagnosis apparatusDENSO CORP·Filed 2002·Granted Oct 26, 2004·44 cites·9 claims
- 0793US6386022B1Thermostat malfunction detecting system for engine cooling systemDENSO CORP·Filed 2000·Granted May 14, 2002·28 cites·16 claims
- 0892US7743651B2Method for detecting malfunction of a cooling system based on detected coolant temperatureDENSO CORP·Filed 2008·Granted Jun 29, 2010·12 cites·2 claims
- 0992US5263453AApparatus for detecting misfire in internal combustion engines for vehiclesNIPPON DENSO CO·Filed 1991·Granted Nov 23, 1993·67 cites·6 claims
- 1091US7363804B2Method for detecting malfunction of a cooling system based on detected coolant temperatureDENSO CORP·Filed 2006·Granted Apr 29, 2008·12 cites·6 claims
- 1191US6725710B2Thermostat malfunction detecting system for engine cooling systemDENSO CORP·Filed 2003·Granted Apr 27, 2004·23 cites·16 claims
- 1289US7483781B2Engine control apparatusDENSO CORP·Filed 2007·Granted Jan 27, 2009·18 cites·9 claims
- 1389US6892712B2Leak check for fuel vapor purge systemDENSO CORP·Filed 2002·Granted May 17, 2005·27 cites·14 claims
- 1489US5728941AMisfire detecting apparatus using difference in engine rotation speed varianceDENSO CORP·Filed 1996·Granted Mar 17, 1998·60 cites·29 claims
- 1588US7356985B2Air-fuel ratio controller for internal combustion engineDENSO CORP·Filed 2006·Granted Apr 15, 2008·18 cites·18 claims
- 1688US6968268B2Misfire detector for an internal combustion engineDENSO CORP·Filed 2004·Granted Nov 22, 2005·39 cites·22 claims
- 1786US6832509B2Fuel vapor control system with leak checkDENSO CORP·Filed 2002·Granted Dec 21, 2004·22 cites·32 claims
- 1885US7757649B2Controller, cooling system abnormality diagnosis device and block heater determination device of internal combustion engineDENSO CORP·Filed 2008·Granted Jul 20, 2010·14 cites·10 claims
- 1984US7010967B2Thermostat malfunction detecting system for engine cooling systemDENSO CORP·Filed 2004·Granted Mar 14, 2006·12 cites·13 claims
- 2084US6082337AAbnormality detection apparatus for preventing fuel gas emissionDENSO CORP·Filed 1998·Granted Jul 4, 2000·43 cites·28 claims
- 2181US6148803ALeakage diagnosing device for fuel evaporated gas purge systemDENSO CORP·Filed 1998·Granted Nov 21, 2000·37 cites·59 claims
- 2280US6665608B2Coolant temperature estimation system for estimating temperature of coolant of internal combustion engineDENSO CORP·Filed 2002·Granted Dec 16, 2003·19 cites·10 claims
- 2379US6957570B2Thermostat malfunction detecting system for engine cooling systemDENSO CORP·Filed 2004·Granted Oct 25, 2005·11 cites·3 claims
- 2479US6047674AValve timing control apparatus for internal combustion engineDENSO CORP·Filed 1998·Granted Apr 11, 2000·27 cites·8 claims
- 2576US7168399B2Abnormality diagnosis apparatus and engine cooling system having the sameDENSO CORP·Filed 2003·Granted Jan 30, 2007·16 cites·28 claims
- 2671US7047799B2Thermostat malfunction detecting system for engine cooling systemDENSO CORP·Filed 2004·Granted May 23, 2006·6 cites·29 claims
- 2771US6904792B2Abnormality diagnosing apparatus for vehicleDENSO CORP·Filed 2002·Granted Jun 14, 2005·24 cites·23 claims
- 2870US7024926B2Thermostat malfunction detecting system for engine cooling systemDENSO CORP·Filed 2005·Granted Apr 11, 2006·3 cites·50 claims
- 2970US6637416B2Diagnosis apparatus for detecting abnormal state of evaporation gas purge systemDENSO CORP·Filed 2001·Granted Oct 28, 2003·13 cites·10 claims
- 3069US7140241B2Leak-check apparatus of fuel-vapor-processing system, fuel-temperature estimation apparatus and fuel-temperature-sensor diagnosis apparatusDENSO CORP·Filed 2004·Granted Nov 28, 2006·10 cites·36 claims
- 3168USRE41823ELeak check for fuel vapor purge systemDENSO CORP·Filed 2007·Granted Oct 19, 2010·4 cites·30 claims
- 3267US6085706AValve timing control apparatus for internal combustion engineDENSO CORP·Filed 1999·Granted Jul 11, 2000·20 cites·2 claims
- 3364USRE41660EFuel vapor control system with leak checkDENSO CORP·Filed 2006·Granted Sep 14, 2010·3 cites·37 claims
- 3461US7137295B2Thermostat malfunction detecting system for engine cooling systemDENSO CORP·Filed 2004·Granted Nov 21, 2006·4 cites·36 claims
- 3560US7409284B2Apparatus for estimating air-fuel ratios and apparatus for controlling air-fuel ratios of individual cylinders in internal combustion engineDENSO CORP·Filed 2007·Granted Aug 5, 2008·3 cites·7 claims
- 3659US6564782B2Device for detecting canister deteriorationDENSO CORP·Filed 2002·Granted May 20, 2003·8 cites·27 claims
- 3757US9157336B2Waste heat recovery structure for steel making electric arc furnaces, steel making electric arc furnace facility, and waste heat recovery method for steel making electric arc furnacesWAKAHARA KEIJI·Filed 2011·Granted Oct 13, 2015·1 cites·24 claims
- 3852US7260928B2Diagnostic device for secondary air supply systemDENSO CORP·Filed 2005·Granted Aug 28, 2007·2 cites·2 claims
- 3947US6854452B2Fuel vapor handling systemDENSO CORP·Filed 2002·Granted Feb 15, 2005·3 cites·26 claims
- 4044US7797924B2Abnormality diagnosis apparatus for secondary air supply system of engineDENSO CORP·Filed 2005·Granted Sep 21, 2010·0 cites·22 claims
- 4143US2009165543A1ERROR DETECTION APPARATUS FOR NOx SENSOR AND EXHAUST GAS CLEANING SYSTEM HAVING THE SAMEDENSO CORP·Filed 2008·Application pending·0 cites
- 4238US7397148B2Vehicular anomaly diagnosis systemDENSO CORP·Filed 2003·Granted Jul 8, 2008·2 cites·10 claims
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Identity basis: PatentsView inventor disambiguation (2025Q4-odp release). How scoring works →