Introduction of Product

Introducing AC Servo Press H1F Series Machines

(High-speed Version of Dedicated Servo Press Controller SIT)

Yukio Hata
Junji Matsumoto
Hitoshi Sakurai
Satoshi Tamura

Since it was introduced into the market in 2002 as a pioneer general-purpose servo press, the hybrid AC
servo press H1F series machines are enjoying a high reputation in the market for their high precision and high
productivity.
A dedicated servo press controller SIT4 that enhances these features has been developed and equipped in
the H1F series machines as m/c machines introduced into the market as reported below.

Key Words: Hybrid AC servo press, H1F series, Servo press dedicated controller SIT4, Free motion, Digitiza-
tion of machining information, Visualization of servo effects, Servo press safety standard

1. Introduction
The hybrid AC servo press H1F series is a new concept press
machine featuring high precision and high formability of servo
presses of the direct acting type, as well as high productivity of
general purpose mechanical presses. As such, the machines
in the series have steadily gained market acceptance and have
established a solid position in the market since their introduc-
tion as a new category in the metal machining press field.
This trend has not been confined to the domestic market, but
is spreading to the overseas market as well among Japanese
companies which have moved their production sites off shore
and among overseas manufacturers of precision parts. The
number of machines sold overseas is exceeding machines sold
in Japan.
On the other hand, competitor manufacturers have also been
introducing their general-purpose servo presses in the market
one after another as the market for general-purpose servo
presses has expanded. This trend has prompted the H1F
series to further enhance and differentiate the product features.
Against this backdrop, Komatsu has introduced into the
market m/c machines of the H1F series that can demonstrate
the servo effect further (Photo 1).
Photo 1 H1F series machine

2007 ① VOL. 53 NO.159 Introducing AC Servo Press H1F Series Machines

― 1 ―
2. Aim of Development and the servo press can accomplish various effects in press
machining.
Four years have passed since the new model development To maximize this feature, the selection and operating range
was launched ahead of the other manufacturers. One advan- of the servo motor were optimized, to increase the maximum
tage a pioneer in the market can gain is use of the abundant speed and to significantly reduce the acceleration and decelera-
evaluation data of users that is available to it. Evaluation data tion times.
obtained as a pioneer was sorted and analyzed and the follow- This has increased the productivity by a maximum 40% in
ing results were obtained from this data. “continuous” production and maximum 25% in single process-
Many customers who have purchased the machines have ing of “one safety process” and in alternating-operation
reported servo effects and application techniques. The production with a feeder. The productivity of the m/c
development of the machining techniques is expected to machine enhanced further while the motion in the machining
accelerate further (Table 1). region was the same (Fig. 1).

Table 1 Results of analysis of user evaluations 1 Conventional machine SPM

Respondent M/c machine SPM
Effect

Sliding position
customers
• Increased production, enhanced rate of utilization M/c machine
51
and short initial setup time
Deceleration time
• Stable marking, enhanced drawability and less Conventional
51 (Conventional machine)
machine
machining fluid consumed
• Enhanced precision, longer die life and fewer
112
inspections made
• Fewer processes wider prototyping range 53 SPM increased 10% at
• Lower noise and vibration during machining 94 same pressurizing speed
Deceleration is faster
Total 245 respondent customers with m/c machine Time
(Curvature is acute)
M/c machine is faster even
Deceleration time
On the other hand, users and Komatsu are still going through (M/c machine)
with same motion setting
trail and error on free motion machining, which is the largest
characteristic of the servo press. An important task to Fig. 1 Comparison at same motion setting
enhance the evaluation and market recognition of the servo
press is to establish the effect and verification method (Table (2) Power regenerating system is adopted in all machine
2). types
All the machines adopt the power regenerating system as the
Table 2 Results of analysis of user evaluations 2 servo power supply, allowing the return of energy regenerated
Respondent during free motion operation to the user power source as an
Request and Comment
customers energy saving feature.
• Effects of servo are not fully demonstrated, servo Thus, all the machines in the series are eligible for the
43
is not utilized fully energy saving preferential tax system (Fig. 2).
• Support for machining technique is desired 15
Total 245 respondent customers
H1F60, intermittent operation under 100% load
This m/c machine was developed under the following con-
cepts focusing on servo control that can demonstrate servo
effects further while the current special link configuration of
Bottom
the drive unit that features a high efficiency was retained. Servo press does not consume
dead center
power while stopping at top
1) Enhanced free motion response dead center
2) Enhanced operability Top dead
center
3) Digitization and visualization of machining information
4) Incorporation of most recent servo safety guidelines and CALC
power
compliance with overseas standards 1.5s stopped at top dead center

3. Accomplishment Means Additional 30 to 50%

energy saving by power
Power returned during
power regeneration regeneration!!
1) Enhanced free motion response
(1) Increased maximum speed and short acceleration and
deceleration time Fig. 2 Power waveform during power regeneration
The largest feature of the servo press is free motion that
allows free speed change and free start and stop during motion

2007 ① VOL. 53 NO.159 Introducing AC Servo Press H1F Series Machines

― 2 ―
2) Enhanced operability Conventional machine SIT3 M/c machine SIT4
(1) Adoption of large color monitor screen
Compared with conventional mechanical presses, sliding
motion has to be set and confirmed with the servo press more
frequently on the monitor screen. Thus, good visibility of the
monitor screen greatly contributes to enhanced operability of
the servo press.
The newly developed controller SIT4 is adopted with a large
8-inch TFT liquid crystal color monitor screen, prominently
enhancing both visibility and operability (Photo 2).
(2) Shorter initial setup time and adjustment time Monochrome screen → TFT liquid crystal color screen
The time required for initial setup such as changing the die Display area enlarged about twice,
Enhanced visibility
has been reduced by adding an initial setup stop function to
stop sliding in a preset position when the die is changed in
addition to the normal and reverse rotation select switch for Photo 2 Comparison of monitor screen
sliding which is equipped as a standard specification (Fig. 3).

Normal and reverse rotation select switch

Normal Reverse
rotation rotation

Automatically stopped while

both hands operate ON
Top dead center

Stop point setting function (Setting on screen)

Reverse
Top dead center OFF/ON rotation

Initial setup stop OFF/ON

Normal
Stop position set freely rotation

Manual pulser added as option Initial setup stop

Initial setup time shortened

by “initial setup inching” automatic stop function

Fig. 3 Top and bottom dead center change function and initial setup stop function

The manual pulser function has been prepared as an optional Override function
Override
(Speed regulating
function for work that requires delicate adjustment (Fig. 3). volume function)
Override setting
Down Up
The “override” function allows regulating the overall motion
speed in an operating condition. For example, this makes Motion change
not required
possible for test operation at a low speed on start and at end of Override

production (Fig. 4).

Override setting
Override Down Up

Overall speed regulated

without stopping operation

Fig. 4 Override function

2007 ① VOL. 53 NO.159 Introducing AC Servo Press H1F Series Machines

― 3 ―
 (3) “Dual-language monitor screen selector” function for A function to communicate with an external personal com-
globalization puter serially or through Ethernet has been added, enabling
At overseas production plants, different languages are often detailed analysis of fetched machining information by a per-
used among production engineers, maintenance personnel and sonal computer (Fig. 5).
operators, causing a bottleneck in overseas production.
The new controller allows a change in the display language
on the monitor screen by operating an external operation
(3) Data acquisition
switch while maintaining the on-going press operation status
such as operation, stop and emergency. This enables easy free
motion setting and problem check to be performed by supervi- Data
sors and operators, effectively reducing the time required for
checking and problem restoration (Photos 3 and 4). (1) Sampling conditions
are set Host
PC

(2) Operation
(4) Data reading

Fig. 5 System configuration

The new function allows adjustment and confirmation work

in press machining that has depended on the experience and
knack of skilled operators and inspection of works can be col-
lected and analyzed as digital information, thereby greatly
varying quality control techniques.
This means that prototyping by the research and technical
Photo 3 Monitor display in Japanese departments in Japan can be easily reproduced and checked at
production sites, greatly reducing the time required for initial
setup at production sites from prototyping to high volume
production. Quality control in subsequent processes can also
be achieved easily. This feature will be useful especially at
production sites overseas where personnel cannot be dis-
patched easily (Fig. 6).

Machining know-how
accumulated
Stable quality through
Application to die data management
design and fabrication

Confirmation of
Photo 4 Monitor display in Chinese effects
Host
PC

Easy to adjust
Die design and
3) Digitization of machining information and visuali- fabrication
Visualization of
zation of servo effects machining data
The newly developed dedicated controller SIT4 for Trial and Conventional Difficult to
adjust
servo presses centrally controls all press machines in- error! evaluation
method
cluding servo controls, achieving centralized collection
Effect?
of machining information, which could not be achieved Stable
quality?
by the distributed control system.

Fig. 6 Effect of visualization of machining data

2007 ① VOL. 53 NO.159 Introducing AC Servo Press H1F Series Machines

― 4 ―
 The newly developed functions for digitization of machining (2) Visualization of machining state in sampling function
information and visualization of servo effects are described in The sampling function allows detailed analysis of machining
performed in one cycle.
detail hereunder.
Sliding position, load, angle, states of input and output sig-
(1) “Visualization” of sliding operation in motion setting
nals and other press machining states can be checked in the
function
same graph based on the digital information collected under
The “read” function enables reading of current motion data
specified conditions. This allows a clear presentation of
on the motion display screen. Based on this data, variations
changes made in machining conditions and results of such
in motion settings, sliding positions and speeds, estimated
changes, thereby avoiding a continuation of trial and error as in
cycle count and other items can be confirmed on a personal
the past (Fig. 8).
computer. The “write” function allows writing motion setting
Settings such as low noise motion setting that requires deli-
data modified on the personal computer screen on the press
cate adjustment to decelerate and stop sliding immediately
side again.
before material rupture can be set relatively easily.
This function allows simulation of optimum motion settings
on a desk and greatly shortens the time required for prototyp-
ing and adjustment (Fig. 7).

Simulation results
Motion setting
screen

Tact for forecasted

production is shown

Appropriate touch
speed can be set

Check of timing
with peripheral
devices

Motion display screen

Productivity improved by desk
work through simulation

Fig. 7 Motion display screen

Slide motion diagram Sliding speed diagram

(Result of actual operation) (Result of actual operation)

Waveform of
forming load can be
Sliding speed viewed in detail
variations can be
viewed reliably

Eccentric load is
visible

Height a moment after

touching is visible
accurately

Relationship between adjustment

and result is clearly shown, greatly
reducing prototyping time
Sampling display screen

Fig. 8 Sampling screen. Verification of adjustment results

2007 ① VOL. 53 NO.159 Introducing AC Servo Press H1F Series Machines

― 5 ―
 Using the sequence monitoring function, the output state of Thermal deformation of the machine and die that occurs dur-
interlock timing signals of a feeder and misfeed detection ing continuous production can be checked in time series as
variations of the sliding position and load so that die damage
device can be checked accurately tuned to the machining con-
and wear can be estimated easily.
dition, allowing easy setting of optimum timing. This in turn This feature allows monitoring of inspection, which de-
allows stable production and a sure increase in production pended on inspection of produced works, through digital infor-
quantity (Fig. 9). mation on graph display, saving inspection time. Furthermore,
In high volume production, machining information of numbers of defects can be checked on the graph screen and
accepted parts collected in advance and current machining 100% inspection of works performed in the past can be elimi-
information are compared and quality control indicators can be nated (Fig. 10).
set.

(3) “Visualization” of changes in machining conditions by

trend function
On the trend screen, changes in machining conditions can be
fetched and analyzed every several tens of minutes to every
several hours.

Slide motion diagram Sliding speed diagram

(Result of actual operation) (Result of actual operation)

Touch speed can be

viewed accurately

Height moment Timings of peripheral

after touch is devices and ejector can
visible accurately be viewed

Optimum motion can be set

Sampling display screen while correctly judging timing

Fig. 9 Sampling screen. Setting of timing

Displays maximum load in total

and at left and right, as well as
final limit down position Shows details of
machining defects

Shows counter
count when a defect
is generated

Shows a trend
of machining
defects

Trend of machining conditions is

Trend display screen recorded for checking of machining
defects and die damage and wear

Fig. 10 Trend display screen

2007 ① VOL. 53 NO.159 Introducing AC Servo Press H1F Series Machines

― 6 ―
 (4) Management of multiple presses through Ethernet con- issued an industry standard “Servo Press Safety Requirements
nection and Safety Measures (JFMA TI 103)” for the first time for
The newly developed controller SIT4 is equipped with the servo presses. Following this standard, standardization of
Ethernet function and press machining information of multiple safety requirements for servo presses is expected to spread
presses can be monitored and managed collectively in one throughout the world on a full scale (Fig. 12).
place through Ethernet (Fig. 11).
During the development process of the new controller, a risk
Prototyping assessment was undertaken in accordance with JFMA TI 103
Press factory laboratory and the following was adopted in the controller as safety meas-
ures.
• Brake that outputs a torque meeting the safety require-
ments was adopted.
• Brake actuation conditions meeting the safety require-
Data transfer by
e-mails on the Internet ments were adopted.
Management office • Addition of torque check function
• Photoelectric safety device of Safety Category 4 was
adopted.

(2) Compliance of new servo press controller SIT4 to over-

Multiple presses can be monitored collectively through the Ethernet connection.
Management office can also monitor data simultaneously. seas standards
The new controller SIT4 has acquired certification under the
Fig. 11 Management of multiple presses through Ethernet con- UL standard, as well as the CE mark.
nection The acquisition of these certifications allows the controller
to be shipped to the markets in Japan, China, Asia and the
4) Incorporation of most recent servo safety guidelines and United States, to which shipments of the controller have
compliance with overseas standards already been made, and additionally to the European market.
(1) Trend of safety standards for servo presses and
additional safety measures
In March 2006, the Japan Forming Machinery Association

EU market International METI Ministry of Health, Labor and Welfare U.S.A.

Industrial Safety
Standard A and Health Law OSHA

EN Enforcement
Group standards ISO/IEC JIS
Standard B standards ordinance Compulsory
(Penalty)
Voluntary
Standard for structures of ANSI
Standard C
power press machinery
Application Report
Entrustment
Entrustment

Japan Machinery Federation: “Investigation and Research of Servo Press Technology Institution of Industrial Safety:
Industry standards Standards and Standardization” “Investigation and Research of Promotion for Review
Japan Forming Machinery Association: “Servo Press Standard and of Structural Standards”
Standardization Committee”

2004 2005 2006 2007 2008

Industrial Safety and Health Law
• “Comprehensive Safety Standard for Passed Special
Machinery” Diet session 4/2006
Enforcement 3/2001~
• “Introduction of Risk Assessment of
Proprietors”
Standard for Structures of Power Press 11/2005 Enforcement Public comments Revision
1995 ~
Machinery Entrustment
Technology Institution of Industrial Safety 3/2005
“Investigation and Research of Promotion Report
for Review of Structural Standards”
/2006 8/2007
Japanese Industrial Standards (JIS) JIS Technical
Committee Committees
“JIS Technical Committees” Application Establishment into
Japan Machinery Federation JIS standards
METI “Investigation and Research of Servo Press
Standards and Standardization” 3/2006
Report
Japan Forming Machinery Association Issued
“Servo Press Standard and Standardization Entrustment JFMA: IT103
Committee” Industry standards

U.S.A. ANSI Revision

ISO/IEC (TC199 ISO Committee) ISO

Fig. 12 Trends of safety standards for servo presses

2007 ① VOL. 53 NO.159 Introducing AC Servo Press H1F Series Machines

― 7 ―
4. Future Plans Introduction of the writer

Five years have almost passed since the market introduction Yukio Hata
of the H1F series. Entered Komatsu in 1983.
The new development ushers in digitization of press machin- Currently assigned to Stamping Press KBU,
ing including the servo effect. Komatsu Industries Corp.
We intend to forthwith collect and analyze market needs of
the servo press including a wealth of machining information
generated in the market and to develop new machining proc-
esses and functions in order to perfect products that always Junji Matsumoto
meet market trends. Entered Komatsu in 1967.
Currently assigned to Stamping Press KBU,
Komatsu Industries Corp.

Hitoshi Sakurai
Entered Komatsu in 1985.
Currently assigned to Stamping Press KBU,
Komatsu Industries Corp.

Satoshi Tamura
Entered Komatsu in 2005.
Currently assigned to Stamping Press KBU,
Komatsu Industries Corp.

[A few words from the writer]

Many people have provided their cooperation in collecting user
evaluation questionnaire sheets in the development process of the
new controller. Analysis of each of these questionnaire sheets
has boosted the confidence of the authors in the great potentiality
of servo presses and has emphasized the degree of customer ex-
pectations. The development efforts will be continued in the
future to live up to these expectations.

2007 ① VOL. 53 NO.159 Introducing AC Servo Press H1F Series Machines

― 8 ―