Breakthrough in Japanese Railways 4Electric Trains and Japanese Technology
Asahi Mochizuki

Overview

Figure 1 Historical Acquisition of Technologies

1872 marked the start of commercial railway operations in

1870s

Buying and using products

UK. However, electric railways did not appear until 1890 at

1870s

Hiring Western specialists

an exhibition held in Ueno, 10 years after the start in Europe

From
1870s

Fostering engineers

1890s

Manufacturing by imitation

1900s

Manufacturing under license

1910s1920s

Designing by imitation

1930s
onwardDesigning with own ideas

Japan, nearly half a century after railways had started in thebut only 2 years after Frank J. Sprague (1857–1934) started
running electric streetcars in Richmond, USA, in 1888, which
triggered the rapid spread of electric rolling stocks.
Although the introduction of electric railways in Japanwas not far behind Europe and America, Japan could notdesign or build electric rolling stock. Some of the locomotives

Improvement on designs

imported in the early stages were still in the development
phase, so Japan acquired basic technologies by overcoming
challenges and making incremental improvements.
Japanese engineers also studied overseas and entered into
partnerships with European and American manufacturers

As Japanese started to educate the engineers, they also

to learn the new technologies. By the 1930s, Japaneseactively translated Western technical documents, spreading

engineers had become adept at designing and building

knowledge wider and producing an engineering cadre

electric rolling stock. However, since the two World Wars

who naturally started making use of the knowledge andmade import of material and technologies difficult, Japan wastechnologies they understood.

forced to design and manufacture on its own. By the 1950s,

At that time, even imported passenger carriages andJapan reached a technology level equal to that of Europe

freight wagons had wooden bodies. Thus, it was only

and the USA but was still behind in terms of speed. However,natural that Japanese, with a history of woodworking,while Europe and America remained at a standstill, Japan

were able to imitate these carriages from an early stage.

went on to develop the shinkansen, contributing to electric

However, locomotives, bogies, and wheel-sets continued torailway technology and rail redevelopment worldwide.

be imported.
It was 1893—about 20 years after the introduction of

Shift to Domestic Production in Japanrailways—when the first steam locomotives could be

Around 1870, Japan was eagerly importing new technologies

manufacturing was launched in 1901. Production of steel—from the West to make life easier, and the social climate of

the main material of locomotives—started with the opening

Japan was accepting of new technologies. However, peopleof the Yahata Steel Works.

built by complete imitation at the Kobe Works. Full-scale

did more than just use them—Japanese engineers wereAbout another 20 years would pass before Japanesestrongly motivated to study and create their own advances.

designed and manufactured their own steam locomotives

Western engineers were hired to both operate thein 1914. By that time, more than 40 years had passed since

new technologies and to train Japanese engineers. At thethe introduction of railways in Japan. The developments intime, the government sent students overseas to learn theJapanese railways can be expressed as shown in figure

new technologies. In many cases they were sent abroad

1. While there are some slight differences, technologies

in conjunction with placing orders for imported products.

for fields such as shipbuilding, civil engineering, andWhile the overall number was small, they replaced foreignarchitecture were gained in a similar manner.

engineers on return to Japan.

Japan Railway & Transport Review No. 55 • Mar 201030

Breakthrough in Japanese Railways 4

Sprague tram at industrial exhibition in Ueno, Tokyo (The Railway Museum)

Introduction of Electric Rolling Stock
Technologies
Electric traction started in Europe and the USA as tramcars
and subway locomotives in the 1880s powered by 500/600
V DC.

Scale model (top) of tram and actual bogie and traction motor at The Railway
Museum in Saitama Prefecture		
(The Railway Museum)However, the low-voltage DC feed made it difficult todevelop electric locomotives with sufficiently high output
to replace steam locomotives for hauling heavy passenger
and freight trains, and to introduce electric traction on lines
with steep grades and long tunnels where steam operation

Fujioka, who was Chief Engineer at Tokyo Electric Light

was difficult. Trials were made with high-voltage DC-motor,(now Tokyo Electric Power Co., Inc), imported a Sprague

but commutation of DC motor did not go well, so AC feeds

tram in 1890, which he ran at an industrial exhibition in

were developed but caused problems with control of speed

Ueno, Tokyo. Power was supplied from Tokyo Electricand traction effort of AC motors. In addition, supply ofLight’s power station.

three-phase AC through overhead lines and pantographs

Meanwhile, Imperial College of Engineering graduate

was complex and finally AC commutator motors (very

Sakuro Tanabe (1861–1944), who had led the work on

similar to DC motors) were used at lower frequency. AC

the Lake Biwa Canal, visited the USA in 1888 with Kyoto

supply only became reliable and problem-free much later

entrepreneur Bunpei Takagi just before completionin the 20th century.

of the canal. During their stay in the USA, they visited a

Many attempts were made using different current

hydroelectric power plant which was under development

collection and power transmission methods for electric trams

after an introduction by Sprague. On returning to Japan inwhich started operation in 1881. However, Sprague found

1891, Tanabe built the Keage Hydroelectric Power Plant

commercial success with a nose-suspension drive reduction

using the Lake Biwa Canal. Takagi and others ran powergear method and a pole-pushed current collection methodfrom the plant to trams in Kyoto in 1895. He was president

in 1888. The so-called Sprague system spread rapidly in theof the tram company and Fujioka oversaw technical areas,

USA, followed by practical application for electric multiple

later becoming a technical instructor for electric railways

units (EMUs) in 1897, leading to EMUs taking the railway

throughout Japan.
Japan’s first electric tramcars were 6-m long and 2-mworld by storm.
Ichisuke Fujioka (1857–1918) studied electric engineering

wide with one bogie powered with one traction motor (550

under professor William E. Ayrton (1847–1908) at theV, 25 hp). The motor was by GE of the USA and the bogie

Imperial College of Engineering (predecessor of today’s

was also American. The body was built in Japan. A traction

University of Tokyo Faculty of Engineering). He travelled

motor and bogie are preserved at The Railway Museum into the USA in 1884 where he met Thomas Edison (1847–

Saitama Prefecture.

1931) and received advice on domestic manufacturing ofelectrical equipment.

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Japan Railway & Transport Review No. 55 • Mar 2010

Development and Domestic Production ofElectric Rolling Stocklater from the USA too. However, rail passenger levels wereTrams also began running in Nagoya in 1898, followed by

Manufacturing of traction motors star ted at thethe Keihin Kyuko Daishi Line in 1899 and Tokyo and Osakagovernment railways Oi Works in 1916 by disassemblingin 1903. Kobu Railway started running EMU trains in Tokyo

English Electric traction motors, making detailed drawings,

in 1904 as the first multiple-unit-control operation. Kobu’s

and manufacturing exact copies. Engineers had previously

EMUs became the predecessors of the government railways’

acquired good technical skills through service repairs, so

EMUs, as the company was nationalized in 1906. Most of thethey reached the quality level of imports right from the start.

electrical equipment and bogies were imported.

In 6 years, 296 motors were built and most of the government

rising and more trams and EMUs were needed, driving thestart of domestic production.

railway’s traction motors were ordered from Toshiba, Hitachi,

The EMUs on the Paris Metro opened in 1900 were also

and Toyo Electric by 1920.

Sprague type, and the first were very similar to the EMUs in

The shift to domestic production of electric equipment forJapan at the time. In other words, trains running in the Westpublic trams was going forward at the time, but these wereand in Japan were at about the same technical level.
During these developments, Tanaka Engineering

simply exact copies. Electric equipment of private-railway

Works (predecessor of Toshiba) examined the imported

high-speed EMUs was comprised mostly of imports. The

technologies and started manufacture of traction motors,

main reason was quality, but imports also cost less. Whilecontrollers, and bogies in 1899 for use on the Daishi Linethe government railways shifted to domestic equipment aselectric railcars in 1901. Although domestic manufacture

part of national policy, the same logic did not always apply

had started, most items were still imported perhaps because

to private railways.

of production quality and capacity problems. Even so,

Domestic Production of Electric
Locomotives

domestic production started soon after trams started running
in Japan.
As trams came into widespread use across Japan,
suburban EMUs like those of Kobu Railway also became

As mentioned, AEG electric locomotives were imported incommon in urban areas; Hanshin Electric Railway was

1912 to electrify the section of continuous steep grades

electrified in 1905; Nankai Railway in 1907; Keihan Electric

between Yokokawa and Karuizawa. However, major design

Railway, Hankyu Railway and others in 1910. The bogies

changes at manufacture resulted in many failures after theand major electrical equipment were imported from Generalstart of operations because electric locomotive technology

Electric (GE), Westinghouse, Siemens-Schuckert, andwas still not well established even in the West.
Locomotives were already equipped with electric brakes

English Electric.
The electric locomotives had already been used in mines

using either dynamic or regenerative braking, but neither

and in other excavations, but they were first used in main

was reliable. The frequent breakdowns resulted in manyline operations in 1912 with Abt rack-and-pinion electric

retrofits. From 1919 to 1922, four-axle electric locomotives,

locomotives crossing the steeply graded Usui Pass. They

including traction motors, were designed by the government

were built by Allgemeine Elektrizitäts-Gesellschaft (AEG)
of Germany, but lacked power and were prone to trouble
because sufficiently reliable electric locomotive technology
was not yet established in Europe. In conjunction with thisorder for electric locomotives, the government railways
engineers studying in Germany conducted research
into electric locomotives in 1909 along with overseeing
production. In this way, many engineering graduates of theImperial College of Engineering often studied abroad, moving
between newly established electric railway companies andmaking technical selection of imports.
Meanwhile, Toshiba entered into a technical partnershipwith GE in 1909; Toyo Electric with English Electric in 1916;
and Mitsubishi Electric with Westinghouse sometime before
1925, marking the start of domestic design of electric
locomotives and EMUs.

Hitachi’s Class ED15 was the first domestically built electric locomotive
completed in 1924 and delivered to government railways in 1926
		(The Railway Museum)The outbreak of WWI cut off imports from Europe andJapan Railway & Transport Review No. 55 • Mar 201032

Breakthrough in Japanese Railways 4

railways and manufactured at the Omiya Works by imitating

way they naturally came to be intimate with the technologies.

imported three-axle locomotives, but stable operations were

The GE locomotives were the most reliable but wereachieved through original modifications.

the most expensive. Hitachi engineers had been closely

Operation of electric locomotives started on theobserving locomotives made by American manufacturers

Yokosuka and Tokaido main lines in 1925 with electrificationand completed the company’s own Class ED15 electricof the Tokyo to Kozu section, but the locomotives were all

locomotive in 1924. It replaced American electric locomotives

imports mostly from English Electric but with some fromin 1926 and was more reliable.

GE, Westinghouse, and Brown Boveri. Early electricWith this opportunity, Japanese builders started working

locomotives broke down so often that they had to beon their own designs but the government railways wascoupled with steam locomotives as a backup. To drive

worried about the diverse range of designs. They met withand maintain them, the Japanese railway engineers were

the Japanese manufacturers and took the lead in promoting

forced to work painstakingly, and they said in later years,

a standardized design of electric locomotives. Following thisthey were able to ‘gain good knowledge of the technologies

policy, Hitachi, Toshiba (which had a technical partnershipas a consequence’. If the imports had not broken down,with GE) and Mitsubishi Electric (which had technicalengineers would simply have driven them and not looked

partnership with Westinghouse) and others conducted

closely at the detailed parts. When troubles occurred, thejoint design. Their first Class EF52 electric locomotive wasengineers from import agents could not satisfactorily deal

completed in 1928 under the leadership of government

with them and railway engineers conducted repairs andrailway’s Kiichi Asakura (1883–1978).

made modifications so that failures would not reoccur. In thisAsakura was a famous designer of Japanese steam

1500

880

3615

2115

Figure 2 First Domestically Produced Jointly Designed Standardized Class EF52 Electric Locomotive

860
6.9

1800

6.9

2000

1250
13.4

1880 13.4
4400

2520

13.4 1200

1200 13.4
9320
18,80020,800

2520

13.4
4400

1880

13.4

2000

6.9

EF52 Electric Locomotive							

33

1800

6.9

(The Railway Museum)Japan Railway & Transport Review No. 55 • Mar 2010

locomotives, but he observed electric locomotives for 2 years

voltage from 600 to 1200 V in 1914. The trains’ electricalin Europe and America. He oversaw building of Japaneselayouts were made in the USA, and the breakers on theseelectric locomotives, realizing that the nose-suspension drive

circuits were connected in series using two devices. Thisand leading bogies had advantages over other systems.

seemed like a stopgap measure, and was not a technology

Hitachi’s Seiji Mitsuida, a production engineer participating

to be admired.

in the joint design, observed American railway companies

American electric railway track using trams or EMU evenand manufacturers in 1926 on referral from Asakura.

today totals more than 300 km at 1500 V DC. Japan, on

Observation at European and American manufacturers

the other hand, has more than 10,000 km of such track. In

was limited but those manufacturers accepting government

the USA, direct current is mainly for urban transport, and israilway’s engineers treated him favourably. Since Mitsuida

mostly 600 to 750 V. American railways using 1500 V DC

laboured over designing and building an original electric

today still struggle to handle the high voltage, so high-voltage

locomotive before going to the USA, he was able to learn

direct current technology with a sufficient record for EMUs

the essence of design. Mitsubishi Electric’s Saneyoshi Hirota

probably did not exist in the USA at the time.

was another participant in the joint development who also

With 15 0 0 V adoption in Japan in 192 3, local

visited the USA in 1928 where he made observations mainly

modifications were added. Japanese original designs wereat Westinghouse.

also developed.

Full-scale Production and Standardization ofElectric Equipment for Electric Rolling Stockdifferent manufacturing methods made handling andAs previously mentioned, imports of products such as

EMU traction motors. Toshiba, Hitachi, and Toyo Electric

electric equipment were cut off as a result of World War I

started building traction motors for government railways inwhile demand for EMUs increased, creating a need for full-1920 but differences between makers caused problems

scale domestic production, as was happening for trams.

with coupling rolling stocks with traction motors with different

After the war, imported EMUs were often used by private

characteristics. Moreover, the different designs, lack ofrailways for intercity and suburban trains due to their highdetailed drawings, different parts, etc., caused headaches

speed and reliability.

at inspection and repair.

The different timing of equipment introductions andmaintenance complex, so standardization by joint design
started around 1925. The first target of standardization was

The 1920s saw the production of many Japanese-

To solve these problems, government railways took thedesigned traction motors and controllers but most werelead in standardization by manufacturing companies, which

Western-designed or derived from Western-designed

included some companies such as Toshiba, Hitachi, Toyo

products. The basic design for EMU multiple unit control,

Electric, and Mitsubishi Electric, that were involved in the joint

automatic traction control, electromagnetic switch control,

designing of traction motors. There were some companies

and other areas was American.

which had partnerships with GE, Westinghouse, and English

As an example, a private railway engineer who had

Electric, while some others were using their own uniquereturned from studying abroad intended to use GE

designs. This made provision of detailed structural diagrams

products for EMUs on a trunk line with continuous steep

difficult. Moreover, all electrical manufacturers tended togrades constructed between Osaka and Ise around 1930.

be more secretive about their designs than manufacturers

However, Mitsubishi Electric brought the full influence of theof steam locomotives, so they would not provide detailed

Mitsubishi Group to bear, demanding domestic production

structural diagrams. As a consequence, the government

and use of Mitsubishi Electric products. Hirota, a designer

railways had problems determining the best design andof traction motors for Mitsubishi Electric was a member ofnone of the Japanese companies wanted to be subject tothe government railways’ joint design team and succeededa determination about which company was superior. In thein designing the Mitsubishi traction motor for the Osaka-

end, government railways decided only one joint design

Ise high-speed EMUs without any problems. However, hewould be built jointly by four companies including Mitsubishi.

did not succeed in designing the controller. Since it used

The individual companies all showed reservations about

electric braking, the design had to be implemented using

carrying out joint design. Government railways, however,technology from Westinghouse who had a partnershipinsisted on unified design, and it went full out in pushingwith Mitsubishi Electric. Many problems after the start ofthe project forward as it would benefit domestic production.

operations forced repeated improvements, giving Hirota

The first product was the 100-kW class MT15 traction motor.

and Kintetsu’s (the railway company) engineers intimate

Design was based on technologies of developed nations,knowledge of the technology.

but it proved to be a Japanese-original design achieved bysifting through the technologies of the individual companies.

Meanwhile, the government railways raised the feed

Japan Railway & Transport Review No. 55 • Mar 201034

Breakthrough in Japanese Railways 4

EMU controller technology is unique, and unlike traction

increased quality while securing some assured level ofmotors, it requires usage experience even when just copyingorders instead of dominant market share. So none of theother designs. As a result, no unique Japanese designs

manufacturers avoided participation. Many of the engineers

were built for many years and reliance on imports lasted

from manufacturers felt that, by participating in joint design

a long time. However, licensed production did lead tomeetings and competing with each other, their technicaloriginal design and manufacturing in 1923 and became

levels were improved. Since new designs were needed

standardized in 1931 when the CS5 standard controller was

periodically, standardization was not a major hindrance tobuilt by Toshiba, Hitachi, Toyo Electric, Mitsubishi Electric,

technical progress.

and Kawasaki Heavy Industries based on technologies

This joint design system had benefits for both thefrom GE, Westinghouse, and English Electric. This controller

operator and manufacturers. So, while there was someremained in production for 20 years, indicating the success

indecision at the change from JNR to JR with privatization,of the design.

the system is followed even today, contributing greatly to

At this time, private railways were often using imports.

technical progress. Private railways are often used as the test

However, once they started using domestically manufactured

venue for manufacturers, but they benefit by gaining accessproducts, private railways tended to continuously order fromto government railways’ high-quality standard equipment.

specific companies, which held back standardization.

However, the success of the joint design system isgreatly affected by the qualifications of the project leader.

Joint-design System

The design leader determines the merits of the individual

Joint design had big benefits for government railways

to pick and choose the advantages of companies. Thus,

but there were worries that it would not produce the best

design engineers are fostered from those with maintenancedesigns and might impede competition and creativity. Whileworksite experience and experience in design improvement,

described as ‘joint design’ there was competition at thesuch as pursuing causes of and dealing with factors suchbasic design stage when the manufacturer with the best

as breakdowns.

companies’ proposals and requires a sense of balance

proposal was selected. Competition was thus fierce, andDevelopment of Original JapaneseTechnologies

optimal proposals were created. Manufacturers were able
to make proposals that were to their benefit even if they
were not chosen for the base design. Every now and then,such proposals were adopted by the JNR leader. Also,

World War II and the immediate pre and postwar years

sometimes manufacturers were able to access technologies

were blanks in terms of technical development, whichof other participating companies, thereby benefiting fromrestarted again around 1950 based on Western technology.

The Series 151 DC EMU running 556 km between Tokyo and Osaka in 6.5 hours from 1958 was the culmination of new technologies
developed by private railways and manufacturers from around 1950				
(The Railway Museum)

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Japan Railway & Transport Review No. 55 • Mar 2010

thyristor later outstripped the West. With development ofsemiconductor thyristor, chopper control for DC EMUs
was quickly developed, and electric dynamic braking
switched to regenerative braking. Practical use started
with subways that could handle stop braking with relatively
small-capacity choppers.
Concurrently, JNR engineer Yuji Kawazoe (1933 –)worked as leader in replacing AC electric locomotive tapchangers with thyristor phase control to achieve contactlesscontinuous control in 1965. Furthermore, an AC electric
locomotive with external commutating converters that could
be used for AC regenerative braking on sharp grades was
put into commercial service in 1968.

First mass-produced Class ED70 AC locomotive in 1957			
(A Hundred Years of Progress in JNR Rolling Stock)

Technologies to use these power semiconductors inelectric rolling stock were developed completely throughoriginal Japanese technologies. However, semiconductor
developments, in many aspects, were advanced by the

However, the rebirth was not in the form of imports; rather,needs of electric rolling stock. As gate turn off (GTO) thyristor

original designs created by using select information gained

was developed, variable voltage variable frequency (VVVF)

from the West through technical partnerships progressed

inverters came into practical use for DC EMUs, three-rapidly. As one example, JNR Chief Engineer Hideo Shimaphase asynchronous motors appeared, and EMU systems(1901–98) took the lead in ongoing research into high-became mostly contactless, greatly reducing maintenance.

speed bogies, leading to rapid development of EMUs forPulse width modulation (PWM) converters were developedmass transport of commuters as well as long-distancefor shinkansen and other AC EMUs, and AC regenerative

high-speed intercity travel.

braking could be used freely as self-excited converters,

The main technologies were two motorized cars making

making shinkansen much lighter.

up one unit for high acceleration and deceleration, use of

Synchronous motors and induction motors were usedelectric brakes from high speed to full stop, and long trainin Europe from the age of thyristor because commutation,

sets giving comfortable rides thanks to bogie-mounted

such as with TVG-PSE DC motors, was not good andtraction motors and air springs. Such base technologies

maintenance was a heavy chore. Also, Commutation was

supported Japan’s unique railway system form where EMUs

essentially difficult with German and other AC commutator

are the main force of passenger transport, forming the

motors. In Japan, the good quality of commutators andfoundation for development in a country that has one of thebrushes enabled delays until GTO thyristor was developed;

largest numbers of EMUs in the world.

Germany put PWM converters into use with thyristor before

The West had been using AC electrification from theJapan, but experienced many problems that were finally

early 1900s, but it was mainly low-frequency AC. Whensolved using Japanese GTO thyristor.

commercial frequency AC electrification was put to practical

Development of Technologies for Higher
Speedsuse in 1951, rolling stock with AC traction came into practicaluse. Japan started research into AC traction in 1953 andconsidered importing European technologies but failed
negotiations forced domestic development. A prototype

Main lines connecting Japan’s major cities were mostly

AC electric locomotive with mercury rectifiers was built incompleted by the 1950s, but routing through the many

1955, and full-scale commercial operation of AC electric

mountainous areas, resulted in many steep grades andlocomotives began in 1957.

tight curves. Because of high population density, there wereElectric locomotives with mercury rectifiers weremany level crossings. The many level crossings required amainstream at first but silicon diodes developed in 1958

train emergency braking distance of 600 m.

were soon in use in EMUs. Dual AC/DC EMUs were being

As a result, speed could only be increased to about 120

manufactured in 1960 and came into commercial service

km/h and today’s maximum speed on some sections without

in 1961. AC-DC dual system EMUs were deployed rapidly

level crossings is still 160 km/h. The shinkansen achieved

across Japan. The development of technologies for powerhigh-speed operation by using gentle curves and gradients,

semiconductors was achieved at almost the same time as inand by eliminating level crossings. When the shinkansen was

Europe. However, Japanese advances in semiconductor

being planned, JNR engineers received some information

Japan Railway & Transport Review No. 55 • Mar 201036

Breakthrough in Japanese Railways 4on the results of 331 km/h high-speed tests in France inbogie vibration. In 1948, pre-war EMU designs reached

1955, and technical development for running stability at

maximum speeds of 119 km/h, and a record of 145 km/h

high speed was diligently addressed. In 1947, Hideo Shima

was set using new EMUs in 1957. In 1959, Series 151 EMUs

established a forward-looking study group on high-speed

reached maximum speeds of 163 km/h, and a world record

Figure 3 Bogie for Series 0 Shinkansen

Shinkansen EMU IS-type bogie					(JNR Rolling Stock Design Office)Figure 4 Example of Controlled Tilt (JR Shikoku Series 2000)

Tilting beam

Pneumatic cylinder for control
TilterBogie frame

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Japan Railway & Transport Review No. 55 • Mar 2010

EMUs on the Chuo West Line in 1973. Europe was using
active tilt control. However, due to that, introduction ofpendulum EMUs was delayed in Europe. Japan adopted
natural pendulum by centrifugal force first. Active control wasadded later, eliminating poor ride comfort due to delayed tilt
and contributing to speed increases on conventional lines
across Japan.
More recently, body inclination using simple air springs
has been used on both the Tokaido Shinkansen and somenarrow-gauge lines.

Conclusion
Electric rolling stock was developed in the West from thelate 19th century through the early 20th century and wassoon being built in Japan. These developments cameabout due to people such as electric engineer Ichisuke
Fujioka and entrepreneur Bunpei Takagi being greatly
influenced by their experiences in the USA. Later advancescame from visionaries like Kiichi Asakura and Hideo Shima
who, despite being a steam locomotive designer, actively
learned Western electric rolling stock technology, brought

Series 381 Shinano limited express. This series was the firsttilting EMU (A Hundred Years of Progress in JNR Rolling Stock)

together the technology of the domestic manufacturers, andstarted domestic production to build Japan’s technology
base and finally give birth to the shinkansen.
National railways are disappearing in countries acrossfor narrow gauge of 175 km/h was set in 1960. Those tests

the world and countries other than Japan with advanced

provided the fundamental data for later development of high-railway technology where infrastructure and rolling stock

speed shinkansen bogies.

are operated together are becoming scarce. As a result,

At the same time as high-speed tests on conventional

there are high expectations for Japanese railway engineerslines, scale-model tests started in 1957 at the Railway

meeting the conditions for advancing railway technology.

Technical Research Institute. The difficulty of securing stablerunning at high speeds was confirmed, and full-scale highspeed rolling-stock test equipment that could handle speeds
up to 250 km/h was completed in 1959. Basic tests started
in 1960 using full-scale bogies with changeable structuresand conditions. As a result, various bogies were designed
in 1962 and were given a bench test, followed by a test on
shinkansen test track, giving good stability results at speeds
up to 250 km/h.
Work started on design of mass-produced shinkansen
bogies in 1963. The structure was proposed by JNR
engineer Masahiko Ishizawa (1924–) and was named the IStype bogie. It continued in production until the 1980s.
Shinkansen technical successes were mainly in bogie
technology and AC electric car technology.
Meanwhile, it was proving more difficult to increase

Asahi Mochizuki

speeds on conventional narrow-gauge lines due to grades

Mr Mochizuki is a Consultant at Japan Railway Rolling Stock &Machinery Association. He joined JNR in 1960, where he was involved
in rolling stock maintenance, and designing EMUs, shinkansen, andelectric rolling stocks. Subsequently, he served as a Chief Engineer
Transportation System Division at Toshiba Corporation prior toassuming his current position.

and curves that could not be reconfigured easily. The
solution was high-output pendulum EMUs that could travel
through curves without speed reductions. Tests cars werebuilt in 1970 followed by introduction of Class 381 pendulum

Japan Railway & Transport Review No. 55 • Mar 201038