OUTLOOKThe Outlook of Machine Tool Technological Development:
JTEKT Pursuit of Machine Tool Development Responsive to Globalization
T. OKAYASU

As customer needs diversify and production sites globalize within the machine tool business, we must respondto the low cost advantage held by manufacturers in developing countries and engage in added value competition
with European manufacturers. This report concerns efforts supporting the monozukuri of customers from thestandpoint of technological development, while covering the basics of monozukuri. Along with commodified
JTEKT technologies, I would like to observe what we are enhancing within our technological developments, suchas accuracy stability, improvements in productivity and net productivity rate, the shift to all-purpose, and system
proposals.
Key Words: High-precision technology, low thermal displacement, visualization of production status, skiving

1. Foreword
Japanese machine tool technology has developed tobe the key industry supporting the growth of domestic
monozukuri companies as well as production by thesecompanies. The country proceeded aggressively with thechange to CNC in 1970 to become one of the leadingmachine tool manufacturing countries in the world.
Since then, Japan has been pulled into the automobileand electric industries as well, furthering technologicalinnovation while raising productivity and reliability.
Technologies which support mass production, such as
automation and increased speed, were developed at thistime.
However, as the market diversified in the 2000s,
machine tool technology in Japan became unable torespond to customer needs if merely focused on mass
production. Over the years, it has become increasingly
important to implement efficient production whileaccommodating fluctuations in production volume, atrend made decisive by the great economic stagnation due
to the Lehman Brothers crisis.
Furthermore, competitive monozukuri is unable to be
conducted only within Japan, and therefore competition
has moved into the global market.
This report observes the machine tool situationand looks at various JTEKT engagements within thisenvironment from the perspective of technologicaldevelopment.

JTEKT ENGINEERING JOURNAL English Edition No. 1012E (2015)

2. Changes in the market and strengtheningof technologies with high added value
2. 1 Rise of manufacturers in developing countries
With the development of the CNC unit, machine tools
became numerically controlled, able to perform even themost complex movements with a high level of freedom
and accuracy. Prior to this, machine tools operated
by repeating a number of single motions. Recently,
control technologies have enabled machine tools tomaintain a high level of machining accuracy. Positioning
accuracy, the life of these “mother machines”, as well as
straightness accuracy and perpendicularity accuracy, arealso now able to be offset to a certain degree.
The evolution of CNC facilitated the improvementof performance in machine tools of developing nations
as well, creating an environment where simple machine
operations could be easily achieved by any operator in
any location.
Machine specifications are also improving, as highperformance machine elements (bearings, ball screws,
spindle units, etc.) from Europe and other areas can also
be easily obtained. Figure 1 shows the state of progressof NC machine tools.

2. 2 Trend of efforts within developed countries
and developing countries
At present, market needs have diversified and there
has been a rapid progression of low performance, low
price machines for each model mainly within developing
countries. Therefore, the volume zone of monozukuri has
fallen into a market driven by low price competition.

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Machine tool orders
NC machine tools
NC percentage
88.2

12 000

100
80

72.6

10 000
8 000

60

6 000

40

4 000

20

2 000

The NC was first developed in 1952 in the
United States, and Japan developed
practical NC machine tools shortly afterward.
NC evolved rapidly during the 1970 era.
These machine tools simultaneously
achieved automation and cost reduction,
leading to the expansion of shares both
domestically and internationally.
Currently, the evolution of CNC is further
intensifying global competition.

2005

2004

2003

2002

2001

2000

1999

1998

1997

1996

1995

1994

1993

0
1992

0

NC percentage, %14 0001991

Orders received, 100 million yen−The Outlook of Machine Tool Technological Development: JTEKT Pursuit of Machine Tool Development Responsive to Globalization−

Material: Machine Tool Statistics (published by the JMTBA)

Fig. 1 The development of NC machine tools

High end• Range with high added value
such as high accuracy and processintegration• In competition with European
and Japanese high performancemachines

High performance/High price
Medical electronics

Increase value

Aircraft
Precision die

JTEKT product range

Machining with highadded value remains
with developed countries

Mid-range
Energyperformance/ Infrastructure
Mid-range price Automobiles

Widen range

General components

Low cost zone
• Machines with simple structures
focusing on low price competition
due to the growth of manufacturers
in developing countries

Low performance/Low price[Ranking of machine tools]

Production is focused on
developing countries<Volume Zone>[Bipolarization of market]

Fig. 2 Changing machine tool market

On the other hand, the mid-range performance, midrange cost product lines in which Japanese manufacturers
specialized were being pressed to correspond to declining
prices or convert to machines with high added value. The
greatest issue has become the creation of new added value
suited for the transformation of monozukuri while also
responding to the globalization of our customer range.
Each company is diligently continuing efforts tostrengthen its niche area and stimulate initiatives into newareas.
Developed countries are also actively exploring new
machining methods that developing nations lack, in orderto bring higher added value to the market. It is imperativethat companies enhance machines and develop methods
for more complex and difficult-to-cut materials. Figure 2
shows the structure and transformation of the machine
tools market.

2. 3 Objective of JTEKT machine tools
JTEKT supports the monozukuri of our customers andstrives to propose total solutions for raising value in the

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products they manufacture.
Our company continues to create highly versatileequipment which facilitates variations in production
volume or workpiece type. We have also furthered
the improvement of operational availability without
production loss and evolved controls and systems toenhanced system proposals that can be easily used withina global production environment.
Listed below are the aspects of technologicaldevelopment JTEKT is progressing with in order toexhibit our comprehensive engineering amidst global
competition. From amongst these, I will introduce leading
examples focusing on technologies that will be released
into the market this fiscal year.
(1) Development of technologies able to perform highaccuracy machining(2) Development of machining methods that enablehighly efficient production(3) Visualization of production status and errors and thedevelopment of the control technologies that support
equipment

JTEKT ENGINEERING JOURNAL English Edition No. 1012E (2015)

−The Outlook of Machine Tool Technological Development: JTEKT Pursuit of Machine Tool Development Responsive to Globalization−(4) Development of wheel (tool) technology, as well as
total system proposals that include transfer systems andcoolant units[Example of highly accurate technologies]
The guarantee of stable machining accuracy over long
periods is essential within production equipment for
improving operational availability and manufacturing
products with high reliability.
On the other hand, the constantly changing ambient
temperature surrounding the equipment causes thermal
distortion, which leads to variation of machine accuracy.
JTEKT has therefore been continuing technologicaldevelopment to further suppress and control thermal
distortion. As shown in Fig. 3, 1 to 3 μm displacement
in tool position occurs for every 1℃ change in room
temperature. Consequently, a 10℃ change in room
temperature would cause 10 to 30 μm of variation inmachining accuracy.
As a countermeasure, our company has newly
developed a real time thermal displacement offset
Y +
+

Tool
Z

Workpiece

+

−

− X

technology which measures machine temperature in
real time, immediately analyses variation, and corrects
machine position.
This technology is able to reduce machining accuracy
dispersion of conventional machines by 20%, significantly
raising process capability for the user. Figure 4 shows themechanism and results of this technology.
The behavior of the machine during machining also
has a profound effect on machining accuracy. The effectof the liquid temperature of the coolant flowing within
the machine is also an issue, particularly for grindingthat requires high finishing accuracy. Accuracy variation
can be halved by eliminating the effect of the coolant
liquid temperature. Figure 5 shows an example of thehigh-accuracy body of a grinder without the effect of thecoolant liquid temperature.
[Process integration technology for highly efficient
production]
Process integration technology is an important key
to achieving flexible correspondence to fluctuation in

Large variance in machining accuracy due to machinedistortion caused by changes in room temperature(Machining accuracy changes from 20 to 30 µm when room temperature shifts by 10°C)−

Displacement (µm)/Temperature change amount (°C)
X-axis direction
Y-axis direction
Z-axis direction
Machine displacement
Tool edge Spindle edge Tool edge Spindle edge Tool edge Spindle edge
due to room
temperature change
1.39
3.32
2.13
1.00
1.96
1.38

d

Machining processes
effected by thermal
distortion• Machined hole depth• Machined hole groove depth• Machined face step

• Reverse boring accuracy• Hole position• Boring hole straightness• Face perpendicularity

Temperature data

Fig. 3 Effect of room temperature change on machine heat distortion and machining accuracy

Position control logic
CNC

SensorReal time position control

Machining deviation, µm

SensorInterface

Thermal displacement estimation logic (PSF)
Without offset
With offset

100

80%
0

Y=20

81%
Y=780

Fig. 4 Real time heat displacement compensation and its results
Wheelhead
Isolation cover(1) Bed shape that doesn’t deform easily(2) Isolation cover blocking transfer of coolant
liquid temperature to bed“Reduced thermal distortion by 1/2”

Bed
Coolant routeFig. 5 High accuracy body of grinding machine

JTEKT ENGINEERING JOURNAL English Edition No. 1012E (2015)17

−The Outlook of Machine Tool Technological Development: JTEKT Pursuit of Machine Tool Development Responsive to Globalization−

production volume and machining type while raisingproduction efficiency. Process integration can eliminate
non-machining time such as transfer between machines,
which improves net rate.
For the past few years, much effort has been exerted
into gear machining by skiving on machining centers as aprocess integration technology.
Skiving requires control technology that synchronizes
the spindle and workpiece shaft with a high level ofaccuracy, as well as a spindle and workpiece shaft thatrotate at high speed and with high rigidity. As such,
JTEKT machines utilize our company’s core technologies
such as CNC control and a high-speed spindle. Figure 6
gives an example of integration of gear processes.
[Mechatronics product technology]
Beginning with the management of the entire factory,
control of each piece of equipment is supported by manyof JTEKT’s mechatronics products, which are designatedas one of our important product lines.
Within the market, the shares of controllers such as
the PLC are divided between two major companies.
Our company will utilize our strengths as an equipment
manufacturer to establish a unique position within our
specialty field of production equipment.

Hobbing

ShaperLathe

Hobbing
machineGear
shaperCurrent line

Cutting

JTEKT is strengthening cooperation with groupcompanies and collaborating with Koyo Electronics
Industries Co., Ltd. to establish an assortment of productsthat can be introduced into the controller market. We
are also promoting an “add on” concept for our current
customers and equipment to allow the sale of our products
through the addition of visualized technologies such as
the andon and energy-saving, which we have perfected as
an equipment manufacturer.
Because the signal communication method of existing
equipment differs for each manufacturer, it was extremely
difficult in the past for those other than the original
manufacturer to install additional functions. However, as®
our company’s TOYOPUC -Plus includes an interface
able to respond to all types of communication, it canbe sold as additional function of existing equipment.
Figure 7 shows the concept of adding TOYOPUC-Plus toexisting equipment.

3. Total system proposals
As previously stated, recently the basic elements
which comprise a machine tool have become available
practically anywhere. A large quantity of highChamfering

Drilling

ChamferingmachineMachining
center[JTEKT’s strengths](1) Achieves gear skiving method using amachining center.
Integration of processes other than
tooth cutting into a single machine.
(2) Highly rigid machine structure enables
machining of high module gears.

Proposal

Cutting/Hobbing/Shaper/
Chamfering/Drilling

Integrates all processes

Machining center e500-GS

Fig. 6 Example of gear process integration by skiving method
Andon/Adjustable monitor

×

Andon/Adjustable monitorⓇ

TOYPUC -Plus

JTEKT equipment

JTEKT equipment

Communication method
differs for each PLC
manufacturer, preventing
management functions.

JTEKT equipment
Developed the TOYOPUC-Plus,
which connects different
PLC types.
Added JTEKT functions to othercompanies’ equipment.

Other company equipment Other company equipment

Other company equipment

Fig. 7 Add-on concept of mechatronics products

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JTEKT ENGINEERING JOURNAL English Edition No. 1012E (2015)

−The Outlook of Machine Tool Technological Development: JTEKT Pursuit of Machine Tool Development Responsive to Globalization−

KOYO MACHINE
INDUSTRIES CO.,LTD.

Ball screws

TOYOOKI KOGYO
CO.,LTD.

Hydraulic/pneumatic devices

CNK CO.,LTD.

Coolant supply units
Transfer units

HOUKO CO., Ltd.
KOYO MACHINE INDUSTRIES CO.,LTD.
JTEKT group manufacturers of complete machines

Koyo Thermo
Systems Co., Ltd.
TOYODA VAN MOPPES LTD.

CBN wheels

JTEKT

Mitsui Seiki Kogyo Co., Ltd.

JTEKT

JTEKT

JTEKT/ KOYO ELECTRONICS INDUSTRIES CO., LTD.

All types of high precision bearings

CNC, PLC (Control devices)Strengths of JTEKT/JTEKT group in the foundation technologies of bearings and ball screws
Strengths of JTEKT in control technologies (CNC/PLC) (basic technologies of machine movement)
Strengths of group companies in peripheral technologies such as hydraulic/pneumatic devices, transfer units, and coolant units (supporting system proposals)Fig. 8 Core technologies and Group technologies of machine tools

performance components are sold within the market,
and therefore machine specifications can be enhanced
relatively easily by purchasing and combining highquality components.
Our company and group companies must have function
component technologies necessary for the creationof unique added value. It is also advantageous for amanufacturer to produce fundamental technologies thatcannot be obtained by other companies. The composition
of JTEKT group companies ranges from complete
machine manufacturers to peripheral unit manufacturers,
which enables technologies needed for system proposals
to be obtained from group companies. JTEKT willcontinue to advance technological development whilestrengthening cooperation between group companies andsharing a developmental vision for the future.

high efficiency in order to raise productivity and added
value. We will also encourage versatility to respond todiverse production methods, in addition to promoting
easiness of setup and visualization of equipment. These
actions will enable our company to fulfill the requests ofcustomers throughout the world.
In order to propose technologies for the entire system,
JTEKT will utilize the technologies our group possesses
to strengthen our overall group technologies.
The machine tools business is a backbone industryof monozukuri. We at JTEKT will devote ourselves toimproving the three axes of this business, which include
perception of market needs, vigilance concerning thebenchmarks of other companies, and constant response tochanges.

4. Conclusion
Concerning changes to the environment surrounding
machine tools, I have given the examples of theperspective of a globalized and diversified customer
base, and the polarized perspective concerning the rapid
catch-up of manufacturers in developing nations andcompetition with the technological developments ofEuropean manufacturers. From these perspectives, I haveorganized the development technologies that JTEKT willcontinue to enhance as a machine tools manufacturer.
Our company will strive towards high accuracy and

JTEKT ENGINEERING JOURNAL English Edition No. 1012E (2015)

T. OKAYASU**Managing Officer

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