Koichiro SAWA


Technical Trends and International Standardization Activities in Electromagnetic Relays for Control Systems
Takeshi AOKI Kenjiro HAMADA Kiyoshi YOSHIDA Koichiro SAWA 
Publication:   
Publication Date: 2019/09/01
Vol. E102-C  No. 9  pp. 628-635
Type of Manuscript:  INVITED PAPER (Special Section on Recent Development of Electro-Mechanical Devices)
Category: 
Keyword: 
electromagnetic relayscontact failuresIEC/TC94JIS C
 Summary | Full Text:PDF(1.5MB)

A Method for Evaluating Degradation Phenomenon of Electrical Contacts Using a Micro-Sliding Mechanism — Minimal Sliding Amplitudes against Input Waveforms (2) —
Shin-ichi WADA Koichiro SAWA 
Publication:   
Publication Date: 2017/09/01
Vol. E100-C  No. 9  pp. 723-731
Type of Manuscript:  Special Section PAPER (Special Section on Recent Development of Electro-Mechanical Devices)
Category: 
Keyword: 
electrical contactmicro-sliding mechanismfrictional forceminimal sliding amplitudeinput waveformrising or falling timewear
 Summary | Full Text:PDF(1.3MB)

Commutation Phenomena and Brush Wear of DC Motor at High Speed Rotation
Masayuki ISATO Koichiro SAWA Takahiro UENO 
Publication:   
Publication Date: 2017/09/01
Vol. E100-C  No. 9  pp. 716-722
Type of Manuscript:  Special Section PAPER (Special Section on Recent Development of Electro-Mechanical Devices)
Category: 
Keyword: 
arccarbonerosioncommutationDC motor
 Summary | Full Text:PDF(1.9MB)

A Method for Evaluating Degradation Phenomenon of Electrical Contacts Using a Micro-Sliding Mechanism — Minimal Sliding Amplitudes against Input Waveforms —
Shin-ichi WADA Koichiro SAWA 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2016/09/01
Vol. E99-C  No. 9  pp. 999-1008
Type of Manuscript:  Special Section PAPER (Special Section on Recent Development of Electro-Mechanical Devices)
Category: 
Keyword: 
electrical contactmicro-sliding mechanismfrictional forceminimal sliding amplitudeinputoutput
 Summary | Full Text:PDF(1.9MB)

Fundamental Characteristics of Arc Extinction at DC Low Current Interruption with High Voltage (<500V)
Koichiro SAWA Masatoshi TSURUOKA Makito MORII 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2016/09/01
Vol. E99-C  No. 9  pp. 1016-1022
Type of Manuscript:  Special Section PAPER (Special Section on Recent Development of Electro-Mechanical Devices)
Category: 
Keyword: 
switch for appliancesDC interruption arc dischargearc lengtharc duration
 Summary | Full Text:PDF(1.7MB)

Evaluation of Basic Dynamical Parameters in Printed Circuit Board — Mass, Force, and Acceleration —
Shin-ichi WADA Koichiro SAWA 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2013/09/01
Vol. E96-C  No. 9  pp. 1165-1172
Type of Manuscript:  Special Section PAPER (Special Section on Recent Development of Electro-Mechanical Devices — Papers selected from International Session on Electro-Mechanical Devices 2012 (IS-EMD2012) and other recent research results —)
Category: 
Keyword: 
electrical contactmicro-oscillationfrettingmassforceacceleration
 Summary | Full Text:PDF(3.8MB)

Influence of Arc Discharge on Contact Resistance of AgNi Contacts for Electromagnetic Contactors
Kiyoshi YOSHIDA Koichiro SAWA Kenji SUZUKI Masaaki WATANABE 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2012/09/01
Vol. E95-C  No. 9  pp. 1531-1534
Type of Manuscript:  BRIEF PAPER
Category: 
Keyword: 
contact resistancearc durationmake arcbreak arcelectromagnetic contactor
 Summary | Full Text:PDF(873.5KB)

Effect of Lubricant on Lifetime of Au-Plated Slip-Ring and Ag-Pd-Cu Brush System for Small Electric Power
Koichiro SAWA Yasunori SUZUKI Noboru MORITA Kaoru ENDO Takahiro UENO 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2012/09/01
Vol. E95-C  No. 9  pp. 1465-1472
Type of Manuscript:  Special Section PAPER (Special Section on Recent Development of Electro-Mechanical Devices - Papers selected from International Session on Electro-Mechanical Devices 2011 (IS-EMD2011) and other recent research results -)
Category: 
Keyword: 
slip ringAu platingNi base platingAg-Pd brushlifetimelubricant
 Summary | Full Text:PDF(14.5MB)

Influence of Voltage on Arc Characteristics and Electrode Mass Change of AgNi Contacts for Electromagnetic Contactors
Kiyoshi YOSHIDA Koichiro SAWA Kenji SUZUKI Masaaki WATANABE 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2011/09/01
Vol. E94-C  No. 9  pp. 1395-1401
Type of Manuscript:  Special Section PAPER (Special Section on Recent Development of Electro-Mechanical Devices – Papers selected from International Session on Electro-Mechanical Devices (IS-EMD2010) and other research results –)
Category: 
Keyword: 
electromagnetic contactorelectrical contactarc durationAgNi contactarc energyelectrode mass change
 Summary | Full Text:PDF(2MB)

A Study on Wear of Brush and Carbon Flat Commutator of DC Motor for Automotive Fuel Pump
Koichiro SAWA Takahiro UENO Hidenori TANAKA 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2010/09/01
Vol. E93-C  No. 9  pp. 1443-1448
Type of Manuscript:  Special Section PAPER (Special Section on Recent Development of Electro-Mechanical Devices (Selected Papers from IS-EMD2009))
Category: 
Keyword: 
DC motorflat commutatorbrushcommutation arcwear model
 Summary | Full Text:PDF(2.6MB)

Development of the Lead-Free Brush Material for the High-Load Starter
Ryoichi HONBO Youichi MURAKAMI Koichiro SAWA Hiroyuki WAKABAYASHI Naruhiko INAYOSHI Kyoji INUKAI Takeshi SHIMOYAMA Naoki MORITA 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2007/08/01
Vol. E90-C  No. 8  pp. 1634-1642
Type of Manuscript:  PAPER
Category: Electromechanical Devices and Components
Keyword: 
carbon brushstarterleadweartribology
 Summary | Full Text:PDF(2.2MB)

Consideration on Contact Mechanism of YBaCuO Bulk Superconductor with Deposited Metal Layer
Hiroyuki FUJITA Katsuya FUKUDA Koichiro SAWA Masaru TOMITA Masato MURAKAMI Naomichi SAKAI Izumi HIRABAYASHI 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2007/07/01
Vol. E90-C  No. 7  pp. 1421-1428
Type of Manuscript:  Special Section PAPER (Special Section on Recent Development of Electromechanical Devices (Selected Papers from ICEC2006))
Category: Contact Phenomena
Keyword: 
YBCOpersistent current switchcontact resistancemetal depositionfinite element method
 Summary | Full Text:PDF(1.2MB)

Numerical Study on Electromagnetisms and Material Characteristics of Magnetic Flux Shield for Eddy-Current Type Proximity Sensor
Koichi KOIBUCHI Koichiro SAWA Takashi HONMA Takumi HAYASHI Kuniyoshi UEDA Hiroshi SASAKI 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2007/07/01
Vol. E90-C  No. 7  pp. 1497-1503
Type of Manuscript:  Special Section PAPER (Special Section on Recent Development of Electromechanical Devices (Selected Papers from ICEC2006))
Category: Signal Transmission & Sensing
Keyword: 
proximity sensoreddy-current lossmagnetic circuit numerical analysisplastic magnetic material
 Summary | Full Text:PDF(720KB)

Characteristic Analysis and Enhancement of Sensing Property for Eddy-Current Type Proximity Sensor
Koichi KOIBUCHI Koichiro SAWA Takashi HONMA Takumi HAYASHI Kuniyoshi UEDA Hiroshi SASAKI 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2005/08/01
Vol. E88-C  No. 8  pp. 1696-1703
Type of Manuscript:  Special Section PAPER (Special Section on Recent Development of Electro-Mechanical Devices--Selected Papers from International Session on Electro-Mechanical Devices 2004 (IS-EMD2004)--)
Category: Sensing Devices
Keyword: 
proximity sensoreddy current lossmagnetic circuitnumerical analysisfinite element method
 Summary | Full Text:PDF(1.7MB)

Fabrication Process of Nonarcing Power MEMS Switch
Yu YONEZAWA Noboru WAKATSUKI Yoshio SATOH Tadashi NAKATANI Koichiro SAWA 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2005/08/01
Vol. E88-C  No. 8  pp. 1629-1634
Type of Manuscript:  Special Section PAPER (Special Section on Recent Development of Electro-Mechanical Devices--Selected Papers from International Session on Electro-Mechanical Devices 2004 (IS-EMD2004)--)
Category: Relays and Switches
Keyword: 
arc dischargeMEMSarc suppressioncontact devicecantilever
 Summary | Full Text:PDF(1.2MB)

Development of the Lead-Free Carbon Brush Material for Starters
Ryoichi HONBO Koichiro SAWA Youichi MURAKAMI Hiroyuki WAKABAYASHI Naruhiko INAYOSHI Kyoji INUKAI Takeshi SHIMOYAMA Naoki MORITA 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2005/08/01
Vol. E88-C  No. 8  pp. 1675-1681
Type of Manuscript:  Special Section PAPER (Special Section on Recent Development of Electro-Mechanical Devices--Selected Papers from International Session on Electro-Mechanical Devices 2004 (IS-EMD2004)--)
Category: Automotive Application
Keyword: 
carbon brushlead freestarterwearcorrosion
 Summary | Full Text:PDF(2.8MB)

FOREWORD
Koichiro SAWA 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2004/08/01
Vol. E87-C  No. 8  pp. 1217-1217
Type of Manuscript:  FOREWORD
Category: 
Keyword: 
 Summary | Full Text:PDF(40.6KB)

Characteristics of Flat Commutator on DC Motor for Automotive Fuel Pump
Takashi SHIGEMORI Koichiro SAWA 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2004/08/01
Vol. E87-C  No. 8  pp. 1255-1260
Type of Manuscript:  Special Section PAPER (Special Section on IS-EMD2003--Recent Technical Trend of Electro-Mechanical Devices)
Category: New Technology and Automotive Applications
Keyword: 
commutationarclossgasolineflat commutator
 Summary | Full Text:PDF(977.5KB)

A Proposal of a New Evaluation Scheme of Pips and Craters Formed by Arc Discharges on Electrical Contact Surfaces
Makoto HASEGAWA Koichiro SAWA 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2004/08/01
Vol. E87-C  No. 8  pp. 1277-1280
Type of Manuscript:  Special Section LETTER (Special Section on IS-EMD2003--Recent Technical Trend of Electro-Mechanical Devices)
Category: 
Keyword: 
electrical contactarc dischargeerosionmaterial transferlaser microscope
 Summary | Full Text:PDF(832.8KB)

Application of a Digital Scanning Laser Microscope to 3-D Analysis of Contact Surface Damages
Makoto HASEGAWA Jiro MAKIMOTO Koichiro SAWA 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2003/06/01
Vol. E86-C  No. 6  pp. 932-938
Type of Manuscript:  Special Section PAPER (Special Issue on Recent Development of Electro-Mechanical Devices (IS-EMD 2002))
Category: Discharges & Related Phenomena
Keyword: 
electrical contactserosionmaterial transferscanning laser microscope
 Summary | Full Text:PDF(572.7KB)

Effect of Inert Gas on Surface Film Formation and on Voltage Drop of Sliding Contacts
Takahiro UENO Noboru MORITA Koichiro SAWA 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2003/06/01
Vol. E86-C  No. 6  pp. 891-896
Type of Manuscript:  Special Section PAPER (Special Issue on Recent Development of Electro-Mechanical Devices (IS-EMD 2002))
Category: Contact Phenomena
Keyword: 
sliding contactcontact voltage dropgas adsorptionsurface filmbrush
 Summary | Full Text:PDF(925.2KB)

Effect of Atmosphere Change on Contact Voltage Drop at Sliding Contact
Takahiro UENO Koichiro SAWA 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2002/07/01
Vol. E85-C  No. 7  pp. 1478-1485
Type of Manuscript:  PAPER
Category: Electromechanical Devices and Components
Keyword: 
oxide filmcontact voltage droplow atmospheric pressurephysical adsorption
 Summary | Full Text:PDF(1.4MB)

Experimental Results on Operating Characteristics of Ag, Pd and Cu Contacts in Nitrogen Atmosphere
Makoto HASEGAWA Jiro MAKIMOTO Naoki MINOURA Koichiro SAWA 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2000/09/25
Vol. E83-C  No. 9  pp. 1385-1394
Type of Manuscript:  Special Section PAPER (Special Issue on Current Electromechanical Devices and Their Materials with Recent Innovations)
Category: 
Keyword: 
contact resistancearcnitrogen atmosphere
 Summary | Full Text:PDF(9.6MB)

Recent Researches and New Trends of Electrical Contacts
Koichiro SAWA Makoto HASEGAWA 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2000/09/25
Vol. E83-C  No. 9  pp. 1363-1376
Type of Manuscript:  INVITED PAPER (Special Issue on Current Electromechanical Devices and Their Materials with Recent Innovations)
Category: 
Keyword: 
electrical contactscontact resistancearc discharges
 Summary | Full Text:PDF(1.1MB)

An Influence of Atmospheric Humidity and Temperature on Brush Wear of Sliding Contact
Takahiro UENO Koichiro SAWA 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2000/09/25
Vol. E83-C  No. 9  pp. 1395-1401
Type of Manuscript:  Special Section PAPER (Special Issue on Current Electromechanical Devices and Their Materials with Recent Innovations)
Category: 
Keyword: 
surface filmbrush wearcontact voltage droplubrication
 Summary | Full Text:PDF(2.9MB)

A Plausible Mechanism for Electromagnetic Interference in the Arc Transition
Zhuan-Ke CHEN Toshiro HAYAKAWA Koichiro SAWA 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 1998/03/25
Vol. E81-C  No. 3  pp. 435-438
Type of Manuscript:  Special Section LETTER (Special Issue on Electromechanical Devices and their Surface Science)
Category: 
Keyword: 
EMIsteady arcarc voltage fluctuationionization energy
 Summary | Full Text:PDF(309.6KB)

Arc and Contact Resistance Characteristics of Ag and Pd Contacts in Dielectric Liquids
Toshiro HAYAKAWA Koichiro SAWA 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 1998/03/25
Vol. E81-C  No. 3  pp. 392-398
Type of Manuscript:  Special Section PAPER (Special Issue on Electromechanical Devices and their Surface Science)
Category: 
Keyword: 
arc dischargecontact resistanceAg and Pd contactsdielectric liquid
 Summary | Full Text:PDF(666.3KB)

FOREWORD
Koichiro SAWA 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 1997/02/25
Vol. E80-C  No. 2  pp. 197-197
Type of Manuscript:  FOREWORD
Category: 
Keyword: 
 Summary | Full Text:PDF(62.9KB)

Arc Discharge at Electrical Contacts
Koichiro SAWA Zhuan-Ke CHEN 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 1996/04/25
Vol. E79-B  No. 4  pp. 439-446
Type of Manuscript:  INVITED PAPER (Special Issue on Discharge and Electromagnetic Interference)
Category: 
Keyword: 
arc dischargeelectrical contactradio noiseEMIspectroscopic measurement
 Summary | Full Text:PDF(650.1KB)

The Influence of Oxygen Concentration on Contact Resistance Behaviours of Ag and Pd Materials in DC Breaking Arcs
Zhuan-Ke CHEN Keisuke ARAI Koichiro SAWA 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 1994/10/25
Vol. E77-C  No. 10  pp. 1647-1654
Type of Manuscript:  Special Section PAPER (Special Issue on Recent Electromechanical Devices)
Category: Arcing Discharge and Contact Characteristics
Keyword: 
contact resistanceoxygen effectarc erosionAg and Pd contactsoxide films
 Summary | Full Text:PDF(758.4KB)

An Experimental Study on Material Transfer and Arc Erosion Characteristic of Ag Contacts under Switching Lower Current
Hiroaki MIZUKOSHI Koichiro SAWA Makoto HASEGAWA Kae NIIZUMA 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 1994/10/25
Vol. E77-C  No. 10  pp. 1655-1661
Type of Manuscript:  Special Section PAPER (Special Issue on Recent Electromechanical Devices)
Category: Arcing Discharge and Contact Characteristics
Keyword: 
material transferminimum arc currentarc dischargeorganic gasmolten bridgebounceAg contacts
 Summary | Full Text:PDF(561.7KB)

FOREWORD
Koichiro SAWA 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 1994/10/25
Vol. E77-C  No. 10  pp. 1535-1535
Type of Manuscript:  FOREWORD
Category: 
Keyword: 
 Summary | Full Text:PDF(81.5KB)

Influence of Steady arc Duration on Contact Resistance Characteristics of Ag-Pd30% Contacts
Makoto HASEGAWA Koichiro SAWA 
Publication:   IEICE TRANSACTIONS (1976-1990)
Publication Date: 1990/11/25
Vol. E73-E  No. 11  pp. 1846-1848
Type of Manuscript:  Special Section LETTER (Special Issue on 1990 Autumn Natl. Conv. IEICE)
Category: Electromechanical Components
Keyword: 
 Summary | Full Text:PDF(299.5KB)

Influence of Contact Materials on the Formation of Palladium-Oxides by Mechanochemical Reaction
Makoto HASEGAWA Koichiro SAWA 
Publication:   IEICE TRANSACTIONS (1976-1990)
Publication Date: 1990/04/25
Vol. E73-E  No. 4  pp. 496-498
Type of Manuscript:  Special Section LETTER (Special Issue on 1990 Spring National Convention IEICE)
Category: Electromechanical Components
Keyword: 
 Summary | Full Text:PDF(279.7KB)

A Study of the Formation of Palladium-Oxides Caused by Mechanical Switching Actions
Makoto HASEGAWA Koichiro SAWA Kunio MIYACHI 
Publication:   IEICE TRANSACTIONS (1976-1990)
Publication Date: 1989/04/25
Vol. E72-E  No. 4  pp. 296-298
Type of Manuscript:  Special Section LETTER (Special Issue on 1989 Spring National Convention IEICE)
Category: Components and Materials
Keyword: 
 Summary | Full Text:PDF(227.3KB)

Analysis of Steady Arc Products on Ag/Pd Contacts
Makoto HASEGAWA Koichiro SAWA Kunio MIYACHI 
Publication:   IEICE TRANSACTIONS (1976-1990)
Publication Date: 1988/04/25
Vol. E71-E  No. 4  pp. 276-277
Type of Manuscript:  Special Section LETTER (Special Issue: Papers from 1988 Spring Convention IEICE)
Category: Components and Materials
Keyword: 
 Summary | Full Text:PDF(230.3KB)

A Study on Contact Characteristics of Ag-Pd Alloy Contacts by using Automatic Data-Acquisition System for Contact Resistance
Koichiro SAWA Makoto HASEGAWA Kunio MIYACHI 
Publication:   IEICE TRANSACTIONS (1976-1990)
Publication Date: 1986/04/25
Vol. E69-E  No. 4  pp. 461-463
Type of Manuscript:  Special Section LETTER (Special Issue: Papers from 1986 National Convention IECE Japan)
Category: Components
Keyword: 
 Summary | Full Text:PDF(143.2KB)