Inventor · disambiguated record
Tokio Yamagiwa
Also filed as: YAMAGIWA TOKIO
35 granted patents·1 pending application·788 citations·filing 1980–2002
98Inventor score
Files withHITACHI LTD36
Top patents by PatentIndex Score
36 records- 0194US5305174AMethod of and device for protecting electrical power systemHITACHI LTD·Filed 1991·Granted Apr 19, 1994·106 cites·24 claims
- 0292US5107447AAbnormality diagnosing system and method for a high voltage power apparatusHITACHI LTD·Filed 1989·Granted Apr 21, 1992·88 cites·24 claims
- 0390US5214595AAbnormality diagnosing system and method for a high voltage power apparatusHITACHI LTD·Filed 1991·Granted May 25, 1993·91 cites·5 claims
- 0477US4549132AMethod of testing and verifying a performance for insulation to ground of a disconnecting switch when breaking a charging currentHITACHI LTD·Filed 1983·Granted Oct 22, 1985·19 cites·9 claims
- 0576US5598509AMethod of configuring a neural network and a diagnosis/recognition system using the sameHITACHI LTD·Filed 1994·Granted Jan 28, 1997·38 cites·18 claims
- 0676US4975800AContact abnormality detecting systemHITACHI LTD·Filed 1989·Granted Dec 4, 1990·35 cites·8 claims
- 0774US5982181AInsulated device diagnosing system for diagnosing device based upon partial discharge signal data analyzed by frequencyHITACHI LTD·Filed 1997·Granted Nov 9, 1999·29 cites·10 claims
- 0871US6218627B1BushingHITACHI LTD·Filed 1999·Granted Apr 17, 2001·31 cites·13 claims
- 0969US5601735ALong-sized tubular grounding container unit for gas-insulated electrical device and laser welding device for manufacturing the sameHITACHI LTD·Filed 1993·Granted Feb 11, 1997·28 cites·9 claims
- 1068US6002085AGas insulated switchgearHITACHI LTD·Filed 1994·Granted Dec 14, 1999·31 cites·9 claims
- 1167US6424162B1Insulated device diagnosing system that prepares detection data from partial discharge signal such that periodic elements are given to different specific frequencies of the partial discharge signalHITACHI LTD·Filed 1999·Granted Jul 23, 2002·22 cites·5 claims
- 1267US5473494AElectrical power supply systemHITACHI LTD·Filed 1992·Granted Dec 5, 1995·26 cites·19 claims
- 1366US5699219AGround fault current limiter and method of limiting ground fault currentHITACHI LTD·Filed 1995·Granted Dec 16, 1997·33 cites·14 claims
- 1465US5256976APower apparatus and method of location of a fault in a power apparatus on the basis of attenuation coefficients of electromagnetic coefficients of fault generated electromagnetic wavesHITACHI LTD·Filed 1991·Granted Oct 26, 1993·25 cites·32 claims
- 1563US4829256AInsulation testing device for gas insulated apparatusHITACHI LTD·Filed 1987·Granted May 9, 1989·18 cites·5 claims
- 1660US5627941AMethod of configuring a neural network and a diagnosis/control system using the neural networkHITACHI LTD·Filed 1993·Granted May 6, 1997·19 cites·23 claims
- 1759US5231256APuffer type gas-insulated circuit breakerHITACHI LTD·Filed 1991·Granted Jul 27, 1993·15 cites·13 claims
- 1854US4564721AGas-insulated electrical apparatus with electret for captivating conductive particles and method of removing such particles during assembly thereofHITACHI LTD·Filed 1985·Granted Jan 14, 1986·16 cites·15 claims
- 1951US5929989AOptical pressure detection method and apparatusHITACHI LTD·Filed 1996·Granted Jul 27, 1999·15 cites·8 claims
- 2049US6063997AGas insulated electric apparatusHITACHI LTD·Filed 1994·Granted May 16, 2000·14 cites·18 claims
- 2147US5798484AEnclosed electric conductor arrangementHITACHI LTD·Filed 1994·Granted Aug 25, 1998·17 cites·2 claims
- 2246US6373687B2Gas insulation switchHITACHI LTD·Filed 2001·Granted Apr 16, 2002·3 cites·5 claims
- 2344US4667061AGas insulated apparatus with internal coated insulation layer of high dielectric constantHITACHI LTD·Filed 1985·Granted May 19, 1987·10 cites·5 claims
- 2443US5253180AApparatus and method for diagnosis of power appliancesHITACHI LTD·Filed 1990·Granted Oct 12, 1993·10 cites·21 claims
- 2543US4818825AInsulating spacers for use in gas-insulated electric apparatusHITACHI LTD·Filed 1987·Granted Apr 4, 1989·9 cites·10 claims
- 2641US6538877B2Gas insulation switchHITACHI LTD·Filed 2002·Granted Mar 25, 2003·1 cites·3 claims
- 2741US6292356B1Gas insulation switchHITACHI LTD·Filed 1999·Granted Sep 18, 2001·6 cites·11 claims
- 2838US4306274ADisc ceramic capacitorHITACHI LTD·Filed 1980·Granted Dec 15, 1981·4 cites·9 claims
- 2937US2002163344A1Insulated device diagnosing system and partial discharge detecting methodHITACHI LTD·Filed 2002·Application pending·0 cites
- 3036US6525917B1Power transforming system and methodHITACHI LTD·Filed 1999·Granted Feb 25, 2003·8 cites·3 claims
- 3135US5124687APower apparatus, power transmission/distribution unit, and tripping method thereforHITACHI LTD·Filed 1990·Granted Jun 23, 1992·7 cites·12 claims
- 3234US5689088AGas insulated device, gas insulated switchgear, gas insulated bus line, and cable direct-coupled gas insulated switchgearHITACHI LTD·Filed 1995·Granted Nov 18, 1997·7 cites·12 claims
- 3331US5274205AGas blast, puffer type circuit breaker with improved nozzleHITACHI LTD·Filed 1993·Granted Dec 28, 1993·2 cites·6 claims
- 3431US4672150AConductor supporting apparatus for gas insulated equipmentHITACHI LTD·Filed 1986·Granted Jun 9, 1987·1 cites·8 claims
- 3524US6252763B1Gas-insulated electrical apparatusHITACHI LTD·Filed 1999·Granted Jun 26, 2001·1 cites·7 claims
- 3619US5410243AThree-phase collected type optical current transformerHITACHI LTD·Filed 1992·Granted Apr 25, 1995·3 cites·13 claims
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Identity basis: PatentsView inventor disambiguation (2025Q4-odp release). How scoring works →