Inventor
Seiya Shima
Inventor
Katsuta, JP
Overview
Patents· 20 as inventor
Public. Assignee & technology derived from the patent record. Each patent links to its LexDana page.
B66Bprimary
B66BElevators28%
H02MApparatus for conversion between ac and ac, between ac and dc, or between dc and dc, and for use with mains or similar power supply systems22%
H02PControl or regulation of electric motors, electric generators or dynamo-electric converters14%
G01RMeasuring electric variables8%
Y10STechnical subjects covered by former uspc cross-reference art collections [xracs] and digests8%
H02HEmergency protective circuit arrangements6%
H02JElectric power networks6%
G05BControl or regulating systems in general3%
H03KPulse technique3%
Y02BClimate change mitigation technologies related to buildings, e.g. housing, house appliances or related end-user applications3%
PatentTitleYear
4,870,556'Method and apparatus for controlling power converter'19894,833,586'PWM control for power converter system utilizing pulse dropping at minimum pulse widths'19894,829,416'Apparatus for controlling power transducers of the pulse width modulation (PWM) control type'19894,779,709'Apparatus for controlling AC elevators'19884,780,660'Apparatus for compensating reactive power by current-source type converter'19884,672,520'Current-source power converting apparatus with self-extinction devices'19874,636,932'dv/dt Protection circuit device for an AC-DC converter apparatus'19874,553,640'Controller for elevator'19854,499,986'Control apparatus for passenger conveyor'19854,441,584'AC Elevator control system'19844,387,436'Method and apparatus for detecting elevator car position'19834,361,866'Power converter apparatus'19824,263,988'Speed control system for a motor'19814,256,204'Safety apparatus for elevator system'19814,245,293'Power converter system'19814,171,505'Fault detecting system for a control system'19794,133,018'Thyristor fault-detecting apparatus'19794,099,111'Control apparatus for DC motor'19784,039,866'Thyristor control apparatus'19774,007,414'Current transducer arrangement'1977Career & activity timeline
Assembled from patent assignee/location history and declaration credentials.
1977–1989Patents assigned to HITACHI LTD (20)· patent assignee history
1977–1989Based in Katsuta, JP· patent location history
1981Based in Ibaraki, JP· patent location history
1987Patents assigned to HITACHI ENG CO LTD (1)· patent assignee history
Inventor activity
Assignee and location history derived from the patent record.
Assignees
| Assignee | Patents | Span |
|---|---|---|
| HITACHI LTD | 20 | 1977–1989 |
| HITACHI ENG CO LTD | 1 | 1987 |
Locations
| Location | Patents | Span |
|---|---|---|
| Katsuta, JP | 19 | 1977–1989 |
| Ibaraki, JP | 1 | 1981 |