Electric Power Steering Systems

CAT.NO.S1001E - 2
 Our goal is sensational driving experiences – JTEKT
Offering Greater Peace of Mind with Advanced Driver Assistance Systems
that Enable Experiencing Steering Feel

"Driving," "Cornering" and "Stopping."

Of the three basic vehicle performance functions, our forte is "Cornering."

Committed to producing superior steering equipment,

JTEKT developed the world's first electric power steering (EPS) system in 1988.

Today, our products hold No. 1 market share around the globe.

Electric Power Steering Systems

◉ Collision safety ◉ Functional safety ◉ Preventive safety Reduce accidents Safety

Reliability
◉ Advanced Driver Assistance Systems (ADAS)
◉ Improved driving stability
◉ Autonomous driving
Automation

Improved
Comfort Comfort
Improved New mechanisms
Convenience Convenience
◉ ◉
fuel efficiency
＋ steering performance
Advanced safety
performance

◉ Modularization Resource savings Environment

◉ High fuel efficiency ◉ Recycling
Reduce CO2
◉ Materials substitution
Efficiency

2005 2010 2015 2020 2025 2030

Electric Power Steering Systems 01 02

ADAS
Advanced Driver Assistance Systems
SBW
Steer - by - Wire

Advancements in ADAS Technologies The Evolution of Steering Systems

ADAS
In the near future, transformations will occur not in the vehicle society,
but in the way we live as well Level 2 Level 3 Level 4 Level 5
Autonomous driving level
Thanks to higher computer processing capabilities and more accurate, Advanced Driver Assistance Systems Driver’s initiative System initiative
inexpensive peripheral recognition sensors such as onboard radar and
Reading: OK Sleeping: OK
Monitoring
cameras, modern-day vehicles can detect the periphery and driving conditions Driver’s role (example) * Operation by * Vehicle is controlled by system in order to Driver not required
the driving environment
driver when necessary minimize risk at the time of an emergency
with high precision. Accordingly, the practical application of active safety is
Technologies with
advancing, perhaps best represented by collision avoidance braking. advanced diversification / integration
Additionally, driver assistance systems openly using EPS control, such as
Additional car functions
automatic parking systems and lane departure warning / lane-keeping support
systems, are contributing to the reduction of traffic accidents and the number Peripheral Information
recognition processing Communication
SBW
of related fatalities. These systems are gradually becoming compulsory and are Vehicle centralized
Clutch ECU
the focus of NCAP* ratings. As a result, their widespread use is anticipated. Cameras / Sensors / Radar

In regards to enhancing Advanced Driver Assistance Systems (ADAS), the

Three basic vehicle functions
potential for further advancements from the current Level 2-3 status to fully Passenger
autonomous driving systems that take over driver operation may be feasible with Driving Turning Stopping
vehicle
the expansion of applicable roads predicted for the future. Such technologies
will not only transform the way we drive, but also how we live as well. EPS (w/clutch) (No-link)

* NCAP (New Car Assessment Program)

A public vehicle collision test that involves crashing new cars and assessing the passenger safety level.

Steering system
Steering actuator
Large
+
vehicle Hydraulic power steering

Hydraulic
power source

Method to Software Hardware Complete hardware redundancy

achieve autonomous backup redundancy including power supply
driving level
(JTEKT safety concept) ( JFOPS 2 ) ( JFOPS 3 ) ( JFOPS 4 )

What is redundancy? By duplicating (making redundant) systems for

JFOPS JTEKT Fail-OPerational System
functions required to have high reliability, safety is secured by the remaining
JTEKT concept of safety is defined from 0 to 4. functions even if a component of the system fails (redundant design).

Electric Power Steering Systems 03 04

SBW
Steer - by - Wire

Merits of Steer-by-Wire

Freedom in communication between the driver and system during ADAS operation
(able to freely control both steering wheel and tires)

1. If collision avoidance operation is necessary, not only the steering wheel, but also the tire angle can be controlled appropriately
2. Changes in vehicle orientation are reflected in steering wheel movement, providing steering sensation

Achieving ideal steering properties

1. Improved vehicle response / traceability / stability when changing lanes

SBW

EPS

2. Improved handling at low speeds, improved driving stability at high speeds

Steering wheel angle Large tire angle Small tire angle

Even at the same

steering angle At low speeds At high speeds

3. Conveys the necessary information from the road surface

while blocking out disturbance, thus alleviating driver fatigue

Cobblestone

Vehicle centralized
ECU
JTEKT responds to market demand
No-link SBW enables freedom of layout and
as a steering system supplier
contributes to expanding the vehicle interior space supporting a safe and exciting
vehicle society
No-link SBW

Electric Power Steering Systems 05 06

A Confident, Relaxing Driving Experience… JTEKT products not only realize steering performance matching vehicle requirements (e.g., body, suspension, tires, brakes and
drive-train), our steering systems act as a human-machine interface where the driver's intentions are delivered to the vehicle and
That's what our steering systems provide supplemental / accurate information is transmitted back to the driver, making it possible for the driver to feel "happier," "safer" and
"more comfortable" when driving the vehicle.

Steering System Configuration example : DP-EPS Basic steering operation example : DP-EPS

Definition of steering system: Components used to control (steer) the direction a vehicle is moving; in short,
the equipment for changing the direction of the tires.
Steering wheel
Interface used by the driver to transmit desired direction 1 Steering wheel is turned 4 Motor rotating torque is increased by the
of travel to the steering system reduction gear and transmitted to the pinion
Intermediate shaft
Shaft connecting the steering column to the pinion gear Steering
force
1 2 Torque sensor detects torque signal,
2 Torque sensor which is then input into the ECU 5 Pinion rotating torque (supplemental
Sensor that detects steering torque from the steering wheel
steering torque) on the power-assist side
3 ECU
Calculates the amount of power-assist required
and pinion rotating torque (steering
according to driver’s steering force and vehicle speed signal rotating torque) on the steering-wheel
Steering column 3 ECU adds electric current to the motor side are converted to rack axial force to
Motor Attaches the steering wheel axle inside the cabin, and is equipped based on torque signal and vehicle speed change tire direction
Outputs rotating torque according to the required with an energy absorption mechanism to dissipate impact energy
power-assist calculated and reduce injury to the driver at the time of a collision

Motor electric current

(Motor rotating torque) Pinion rotating torque on
4 Reduction gear power-assist side
Pinion rotating torque on
Gear mechanism that increases the rotational
steering-wheel side
torque generated by the motor and transmits it to
Rack axial
the pinion gear
force
(Turning left) (Turning right)
０ Torque signal
5 Pinion

Rack axial force Pinion

(force applied to change tire direction) Low vehicle speed
High vehicle speed
Rack-and-pinion gear
Converts the rotating motion of the steering wheel
input by the driver to straight horizontal movement to
the rack bar via the pinion gear

Standard System Proposal System Features by Type

UA/A B C D E F
Column-assist Rack-assist
SUV/P-UP
Vehicle segment
UA/A B C D E F SUV/P-UP

Recommended Since the motor and ECU are inside the cabin, Excellent steering performance as the result of
Column waterproofing is not required and minimal friction between the time of
C-EPS
-assist
Application range there is no influence on engine and transmission layout turning the steering wheel and start of rack movement

Steering system

P-EPS Recommended

Rack
-assist DP-EPS Recommended
RP-EPS
H-EPS Application range
Optimum steering system Optimum steering system
for medium- to large-sized vehicles
for compact vehicles with small rack force that require better steering performance
JTEKT EPS systems are compatible for most automobiles, from small vehicles to large SUVs

Electric Power Steering Systems 07 08

C-EPS DP-EPS
R R

● Ideal for compact vehicles with small engine compartment: power-assist unit is located in the steering column ● Rack-assist realizes excellent steering feel with high rigidity and superior dynamic performance

● Introduced as the world's first EPS in 1988 ● System structure with flexible mounting freedom realized by separating the assist unit from the steering wheel axle

● Superior safety, comfort and environmental performance based on technologies and ● Enhanced degree of freedom in specific stroke on the steering-wheel side realized by
  experience accumulated since its introduction   adopting an optimal design to reinforce the assist unit

● System with excellent safety, comfort and environmental performance realized through the application of proven technologies

Column Motor / ECU Column Torque sensor

Torque sensor Intermediate shaft

Stable operation and Compact, lightweight, high-efficiency Compact and simple design and Stable operation and Combined sliding load and rigidity Compact, simple, high-performance sensor
high collision safety performance realized integrated motor / ECU high performance realized high collision safety performance realized resistant to water realized

Motor / ECU
C-EPS system DP-EPS system

Column
Column
Torque sensor

Reduction gear
Reduction gear
Low friction and quiet performance realized Compact, lightweight, high-efficiency
Motor / ECU integrated motor / ECU resistant to water
Intermediate shaft Intermediate shaft

Reduction gear

Torque sensor

Intermediate shaft Rack-and-pinion gear Rack-and-pinion gear

Both low friction and quiet performance realized
Combined sliding load and rigidity High-strength and high rigidity realized Orthogonal / Cross-type worm gear setup improves Pinion with dual-axle support realizes stable
installation flexibility rack behavior

Motor / ECU Rack-and-pinion gear

Rack-and-pinion gear
Reduction gear

Electric Power Steering Systems 09 10

RP-EPS P-EPS
R R

● Rack-assist realizes excellent steering feel with high rigidity and superior dynamic performance ● Small / compact system adopted in response the engine room environment

● Easier installation realized with adoption of high-output, compact reduction gear ● System with excellent safety, comfort and environmental performance realized through

● System with excellent safety, comfort and environmental performance realized through the application   the application of proven technologies

  of proven technologies

Motor / ECU

Column
P-EPS system

Torque sensor Motor / ECU

Motor / ECU Intermediate shaft

Rack-and-pinion gear
Compact, lightweight, high-efficiency
Reduction gear integrated motor / ECU resistant to water Torque sensor

World's smallest packaging developed using Reduction gear

exclusive bearing design 
RD-EPS mass-production experience accumulated
for more than 10 years utilized to develop a new
Compact, simple, high-performance sensor ball screw configuration with excellent Compact, lightweight, high-efficiency
resistant to water realized noise / vibration (NV) performance  integrated motor / ECU resistant to water

H-EPS
R
Column

● Excellent safety, comfort and environmental performance realized using

  an energy-saving hydraulic power steering system equipped with an electric pump
Rack-and-pinion gear
  ● Extremely flexible installation and ability to use for EV driving realized by adopting an independent electric pump
High-strength, high rigidity realized   ● Excellent steering feel and improved fuel efficiency realized through optimum discharge setting (MAP) and special valve tuning
Intermediate shaft

Electric pump / ECU H-EPS system

Torque sensor
(power pack) Column

Helical gear reduces pulsation,

Rack-and-pinion gear and compact / lightweight design realized Intermediate shaft

Motor / ECU
HPS gear
Reduction gear Hydraulic power steering
(HPS) gear

RP-EPS system
Comfortable steering feel realized Electric pump / ECU (power pack)
by optimal tuning of low-flow valve

Electric Power Steering Systems 11 12

 Share No.1
2017
One out of every three vehicles in the world is equipped with JTEKT electric power steering (EPS)
※1
Start of production of
RP-EPS
Unit : 10,000 Unit : 10,000t (CO2)
Total production volume

100 million units

2000 100

PRODUCTION QUANTITY
90
Quantity of carbon dioxide reduction
( April 2015 ) ※2

1988 2004 2011 80

1500 Start of production of Start of production of Start of production of

C-EPS (For small car) RD-EPS DP-EPS 70

2001 2002
Start of production of Start of production of 60
The World First
C-EPS E-VGR
50
1000 (For compact car)

1991 1994 40
Start of production of Start of production of
H-EPS P-EPS 30
500
Start of
Manual Steering 20

Start of 10
Power Steering

1960 1970 1980 1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018

Safer, More Reliable Power Steering Systems to Customers Worldwide Advanced Research & Development Facilities for Producing Next-generation EPS Systems
JTEKT R&D centers exchange information around the world, enabling the company to accurately understand market
demand and provide the newest / best / optimal systems to meet the diversified needs of our customers.

GLOBAL NETWORK
1
4
1 1
7 X-Ray CT scanner Vehicle evaluation in Steering column Power steering system Electromagnetic anechoic chamber
cold regions impact testing apparatus energy consumption
1
measuring apparatus

EUROPE JAPAN Proving Ground Enables Testing / Evaluations Simulating Roads Worldwide
Fully utilizing our knowledge as a world-leading systems supplier, JTEKT conducts driving evaluations and analyses of products installed in vehicles.
NORTH
We exhaustively pursue the highest standards in product safety and operation on a test course capable of simulating various road and weather
AMERICA conditions around the world. As a total systems supplier, our highest value is to provide our customers with products that deliver outstanding
performance and the best quality that help to make automobiles that are more than just fun to drive.

ASIA

SOUTH 2
AMERICA 10
2

Regional headquarters
Steering manufacturing 2
■ Iga Proving Ground ■ Iry JTEKT European Proving Ground
Technical centers 1
・Site area: 500,000m2
・Straight-line track ・Winding track ・Site area: 125,000m2 ・Straight-line track ・Dynamics pad
・Course area: 170,000m2
・Fording track ・Dynamics pad ・Course area: 59,000m2 ・Low friction track
・Combined circuit length: 2,200m ・Noise evaluation track ・Noise and vibration evaluation track
・Dynamics pad area: 43,000m2
・Dynamics pad area: 54,000m2

Electric Power Steering Systems 13 14

OFFICES
JTEKT NORTH AMERICA CORPORATION -Tianjin Branch-
47771 Halyard Drive, Plymouth, MI 48170, U.S.A. Room 1308, The Exchange 2, 189 Nanjing Road,
Tel: 1-734-454-1500 Heping District, Tianjin 300051, CHINA
Fax: 1-734-454-7059 Tel: 86-22-8319-5180
Fax: 86-22-8837-3556
JTEKT AUTOMOTIVE NORTH AMERICA, INC.
55 Excellence Way, Vonore, TN 37885, U.S.A. -Guangzhou Branch-
Tel: 1-423-884-9200 Room 1007, Tower-A Centre Plaza, No.161 Linhexi Road,
Fax: 1-423-884-9295 Tianhe District, Guangzhou, Guangdong 510620, CHINA
Tel: 86-20-3825-1241
PT.JTEKT INDONESIA Fax: 86-20-3825-1248
Jl.Surya Madya Plot Ⅰ-27b, Kawasan Industri Surya Cipta, Kutanegara,
-Chongqing Branch-
Ciampel, Karawang Jawa Barat, 41363 INDONESIA
Room 14-2, Block 3, Jinkai Sincere Center, No.68 Jinkai Road,
Tel: 62-267-8610-270
Northern new District, Chongqing 401121, CHINA
Fax: 62-267-8610-271
Tel: 86-23-6305-6066
JTEKT (THAILAND) CO., LTD. Fax: 86-23-6305-6077
172/1 Moo 12 Tambol Bangwua, Amphur Bangpakong, Chachoengsao, -Wuhan Branch-
24180, THAILAND Room 2211, Office Building, Oceanwide Square,
Tel: 66-38-533-310∼7 No.198 Yuncai Road, Wuhan, Hubei 430022, CHINA
Fax: 66-38-532-776 Tel: 86-27-8556-9691
Fax: 86-27-8556-9690
JTEKT KOREA CO., LTD.
-Seoul Head Office- -Changchun Branch-
Seong-do Bldg 13F, 207, Dosan-daero, Gangnam-gu, Seoul 06026, KOREA Room 1408, Zhongyin Building, No.727 Xi'an Road,
Tel: 82-2-549-7922 Changchun, Jilin 130061, CHINA
Fax: 82-2-549-7923 Tel: 86-431-8892-8680
Fax: 86-431-8892-8902
-Busan Office-
The Korean Teachers' Credit Union Hall 3F, 192, -Hangzhou Branch-
Jungang-daero, Dong-gu, Busan, KOREA Room 3207, Wanyin International Building, No.100 Minxin Road,
Tel: 82-51-463-4830 Jianggan District, Hangzhou, Zhejiang, CHINA
Fax: 82-51-463-4831 Tel: 86-571-8110-6131
Fax: 86-571-8110-6132
TAIWAN JTEKT CO.,LTD.
NO.23, Guangfu N.Road, Hukou Township, Hsinchu, Country 303, TAIWAN JTEKT EUROPE S.A.S.
Tel: 886-3-597-2453 -Office-
Fax: 886-3-597-4687 ZI, Rue du Broteau, CS 70001, 69540 Irigny, FRANCE
Tel: 33-4-7239-4444
JTEKT (CHINA) CO., LTD. Fax: 33-4-7851-2188
-Head Office (Shanghai)-
Room 25A2, V-Capital Building, 333 Xianxia Road,
-Brussels Office-
Changning District, Shanghai 200336, CHINA Bulgicastraat 13, 1930 Zaventem, BELGIUM
Tel: 86-21-5178-1000 Tel: 32-2-541-4765
Fax: 86-21-5178-1008 Fax: 32-2-541-4702

-Shanghai Branch- -Munich Office-

Room 25A2, V-Capital Building, 333 Xianxia Road, Am Soldnermoos 17, 85399, Hallbergmoos, GERMANY
Changning District, Shanghai 200336, CHINA Tel: 49-0-811-8899-628
Tel: 86-21-5178-1016 Fax: 49-0-811-8899-610
Fax: 86-21-5178-1618
-Beijing Branch-
Room 1012, Fortune Building, No.5 Dong San Huan North Road,
Chaoyang District, Beijing 100004, CHINA
Tel: 86-10-6538-8070
Fax: 86-10-6538-8077

PUBLISHER
JTEKT CORPORATION NAGOYA HEAD OFFICE
No.7-1, Meieki 4-chome, Nakamura-ku, Nagoya, Aichi 450-8515, JAPAN Tel:81-52-527-1900 Fax:81-52-527-1911

JTEKT CORPORATION OSAKA HEAD OFFICE

No.5-8, Minamisemba 3-chome, Chuo-ku, Osaka 542-8502, JAPAN Tel:81-6-6271-8451 Fax:81-6-6245-3712

Sales & Marketing Headquarters

No.5-8, Minamisemba 3-chome, Chuo-ku, Osaka 542-8502, JAPAN Tel:81-6-6245-6087 Fax:81-6-6244-9007

The contents of this catalog are subject to change without prior notice. Every possible
effort has been made to ensure that the data herein is correct; however, JTEKT cannot Reproduction of this catalog without
assume responsibility for any errors or omissions. written consent is strictly prohibited.

CAT.NO.S1001E - 2
Printed in Germany ’
17.09-1CCH（’
13.11）