NANOJIN
2022 WINTER

OpticsAutomotive

Reflex Reflector

Head light

Aspheric

Tungstan Carbide

Coaxial lens

Micro texture

Air Spindle

Vibration Cutting

Diamond tool

free-form grinding

Dimand Cutting

Linear motor

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NANOJINEDITOR’S NOTEW

e marked more than a year of the pandemic and had various experiences morethan expected. While it’s not perfect for stressfree communication on the internet, we haveaccepted different types of social media suchas mobile, wireless and smart manufacturing.
We are absolutely realizing a different lifestyleand business now. As well, we can notice somesigns of recovery from several peaks of pandemics.
For us, one of the signs was to join EMOMILANO 2021. We could get many opportunities there with requirement of high value-added manufacturing, though we had to makemany decisions about what and how to exhibit
there. Hence, I would introduce two topics
which show an opportunity for the target having hard problems and strong requirements byintegrating good machine tool performance.
First issue is about lens array fabrication
by ULG-100D. Lens array has strong opticalbenefit and is widely used for a variety of applications such as 5G communications. However, only a restricted mold manufacturing process can be selected because the mold would
be required to have a high-quality surface
despite needing complicated tooling strategy
which is hardly achieved even by the skilled
technician. ULG series, which is one of our lineup of precision machine tools, always propose
the solutions of the productive improvement
for aspheric optics fabrication by developing
the machine tool performance. Particularly,
full-digital control technology is one of significant developments in the last decade.

T

his enables the motion characteristicof the linear and rotary axis to improve markedly and achieve high level
simultaneous control for all axes. Thus,
it is shown in this leaflet as a case study
regarding lens array mold machining byusing above technology.
Second issue is machining a precise
plate applied to the FC stack by UVM450D. FC stack is well-known as key technology for ECO vehicles. It is surprisingly
needed precision machining technology
to get high efficiency. Particularly, quality of microstructure on plate weighs tocreate flow channels with small cornerradius, pitch and high slope because separator plates are precision pressed components affected on the performance ofFC stack.
Additionally, roughness for high hardness
die is also important to eliminate errors
in pressing. UVM series have strong benefits to achieve the above requirement
due to the air spindle and linear-motor
driven system. Here, this leaflet shows acase study regarding machining precise
microstructure mold for hard materials
with a new idea to compensate for tool
contour error on machines.
We always search for an effective
solution by development of machine
tools, software, and peripheral devices
and also hope a good opportunity for
you to think about the next idea. Please
let us know if you have a good interest.
Masahiko Fukuta
Expert / Ph.D. (Eng.)SHIBAURA MACHINE CO.,LTD.

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NANOJINABOUT LENS ARRAYA
FIG.1 CEMENTED CARBIDE LENS ARRAY MOLDMICROLENS ARRAY

Lens array is one of the important industrial productsthat are so pervasive in ourdaily lives. A lens array is an
optical lens consisting of multiple
lenses arranged on a surface, and it
can have various functions such as
focusing, diffusing, averaging, andhomogenizing light depening on
the design. The recent topic “5G” isthe technology that cannot be realized without lens arrays. Lens arrays
are used in a wide range of fields
such as optical communication systems, IT, automobiles, measurement,
solar modules, aircraft, and astronomy, etc. There are many applications
for it, and more efficient productivity
and high-precision are desired in recent years.
LENS ARRAY SHAPE & MOLD MATERIAL

Before we introduce the manufacturing method of lens array mold,we need to talk about mold materials and our machines.
Firstly, there are various moldmaterials for lens array such as ce-

mented carbide, STAVAX, Ni-P
plating, etc. depending on the

FIG.2 LENS ARRAY MOLDINGS

material of the molded product.
There are also various form
shapes of lenses such as simple R,
aspheric, free-form and the number of lenses varies from a few toseveral thousand. Since the moldmaterial, lens shape, and numberof lenses vary from customer tocustomer, it is not hard to imagine
if we use the same manufacturingmethod to every mold, it will notwork very well. In other words, theoptimum manufacturing method
differs for each mold. Shibaura Machine offers variety of options tomake lens array mold to meet customer needs, and customers canselect the best choise from that
options for their mold making process. Shibaura Machine, high precision machining center UVM andultra-precision aspheric machine
ULG are capable of making lens array molds.

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FIG.3 ULG STRUCTURE

FIG.4 ULG-100D(5A)ULTRA-PRECISION ASPHERIC MACHINE, ULG

MICRO LENS ARRAY

U

ltra-precision aspheric machine, ULG series
is equipped with a V-V roller guide way anda linear motor drive for the linear axes. The
V-V roller guide way realizes high rigidity andhigh positioning accuracy. It makes ULG possible toachieve a minimum setting unit of 0.1 nm and 1 nm
step feed for each linear axis. Because of its high precision, the ULG is mainly used for the aspheric lens moldsof smartphones or large-diameter lens molds for single-lens cameras which require ultimate machine precision.

V-V ROLLER GUIDEWAY REALIZESHIGH RIGIDITY AND
HIGH POSITIONING
ACCURACY.
IT MAKES ULGPOSSIBLE TO
ACHIEVE A
MINIMUM SETTING
UNIT OF 0.1 NM AND
1 NM STEP FEED FOR
EACH LINEAR AXIS.

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MICRO LENS ARRAYC

ut surface, making it possible to get
extremely high-quality mirror finished surface. In the case of turning,
it is possible to achieve surface roughness
less Ra“1nm”
TYPES OF LENS ARRAY MANUFACTURING METHOD
The following fig. is representing five typical methods of our lens array mold manufacturing. The horizontal axis indicates theaccuracy of mold (form accuracy, roughness) and the vertical axis is efficiency.
Since in this fig.5 the other factors except
accuracy and efficiency are excluded, it
does not mean that milling and 3-axes-use
work adjustment are superior than other3 methods. Every method has advantages
and disadvantages, and we can propose
proper one to meet the customers’ needs.

FIG.5 LENS ARRAY MANUFACTURING

GRINDING AND CUTTING LENS ARRAY
MOLD BY ULG

Grinding or cutting is adapted
depending on the mold material and multiple options are provided for each. In the case thatmold material is very hard material suchas cemented carbide, grinding is chosen
and others are cutting. In particular whenthe mold material is electroless Ni-P plating,it is possible to use a single crystal diamond tool for cutting, which further increases the degrees of freedom in cutting
arrangements. Electroless Ni-P plating isa material widely used for lens molds.It
has high corrosion and wear resistance,and because of its amorphous structure,no grain boundary steps occur on the

XYZC 4-AXIS COORDINATEDCONTROL METHOD

FIG.6 CUT 4-AXES COORDINATEDCONTROL METHODXYZC 4-axis coordinated control method isapplicable to both grinding and cutting.
The photograph shows the setup forthe grinding process. The lens array mold is
attached to the C-axis by a vacuum chuck,
and when the C-axis rotates, the lens rotates as well accompanied with the rotation of C-axis. In XYZC 4-axis

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FIG.7 MOVEMENT OF LENS

FIG.8 HOW TO ADJUST EACH LENS TO CENTER OF C AXIS.

MICRO LENS ARRAYC

oordinated Control method,XYZ is synchronized with C-axis so that the tool follows therotating lens. Once you set up
the tool and workpiece you can just
wait until all lens is finished.

ment. Turning is the better way to get outstanding form accuracy and roughness,because it does not need the machine of
the complexed movement comparing to
XYZC 4-axis coordinated control method.
In 3-axes-use work adjustment, thecenter of each lens to be cut is moved to
3-AXES-USE WORK ADJUSTMENT
the center of the C-axis to realize the turning process. By using this method, it is posIn XYZC 4-axis coordinated control meth- sible to obtain form accuracy comparable
od, the tool is following to the rotating to a normal turning.
lens surface and it requires machine thecomplexed 4-axis synchronized move-

MILLINGM

illing is generally used in machining
centers though, the ULG is able to domilling by installing a tool spindle.
Milling by the ULG can accommodate
from a few to thousands of lens arrays. A typicalcutting example of milling is a wafer level lens array. Easy to setup, shape stability, and good pitchto-pitch accuracy are the features of the ULG milling.

CAE EUM FUGITAS MAIONSEDI
QUAE
PORIS
FIG.9 MILLING WAFERLEVELLENSSOLOREPEARRAY BY VELULG

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MICRO LENS ARRAY
B-AXIS SHAPER

In this cutting method, B-axis rotate in order to face the tool in the same direction
as cut surface normal direction. By thismethod, it is easy to get strain less surface compared to other method, but since
this method is shaper cutting, efficiency is
not high.

FIG11.C AXIS SHAPER

S

peed of 20000min-1, feed rate of
40mm/min, and finishing depth ofcut of 2um.
The evaluation was performedon the last 50 lenses out of 300 lenses. As
a result, the variation of SAG depth wasunder 1um, the form accuracy was about
0.1um, and the surface roughness wasaround 5nm.

C-AXIS SHAPER

T

his cutting method is similar to milling, however, the tool is mounted on
the C-axis instead of the tool spindle.
Since C-axis is rotated at low speed
compared to tool spindle, this cutting method can avoid the characteristics of the cut
surface caused by the high speed rotation of
the tool spindle in milling.

CUTTING EXAMPLES

H

ere we introduce an example ofmilling of lens array for LEDs.
The workpiece material is copper, the lens shape is an asphericsurface of Φ0.5, and the number of lenses
is 300. The tool is a single crystal diamondof R0.1 mm. The machining conditions weretool rotation

FIG.10 B-AXIS SHAPER

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MICRO LENS ARRAYFORM ACCUARACYNANOJIN 2021 WINTER

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FROM INSIDER #1

ULTRA-PRECISION MACHININGTECHNOLOGY FOR CONTRIBUTINGTO HIGHER POWER DENSITY OF
FUEL CELL (FC) STACKSTEXTK U N I TA K A K U RI YA MAW

ith the challenge of decarbonizing mobility being set forth
as a green growth strategy inconjunction with attaining
carbon neutrality by 2050,
there are particularly high expectations for fuel cell vehicles. Fuel cell stacks, which act
as the power supply unit, are being rapidly developed with higher power densities
for practical use, and one reason for thesedramatic technological innovations is thehigh precision of the flow channels of thethin metal sheets called bipolar plates, ofwhich several hundred are mounted in the
power supply unit. This paper will present anapplication example where ultra-precision

Fig. 1. Unit cell structure of a fuel cell stack5)

machining technology was developed forenabling ultra-precision machining of thismicro-bipolar plate shape.
1.INTRODUCTION
At the end of 2020, the Japanese government declared its policy goal of achieving
a carbon-neutral, decarbonized society by
2050, in which the amount of carbon dioxide
and other greenhouse gases emitted andabsorbed will be net zero. According to 2018
results, about 20% of the country’s 1.1 billion
tons of carbon dioxide emissions came fromautomobiles,1) and so major changes areneeded to adapt to a decarbonized society

in the future. In response, recent years haveseen the rapid development of technologies
in fields such as electric vehicles (EVs) and
fuel cell vehicles (FCVs). Fuel cell vehicles
are fueled by hydrogen and emit only water, and since they are not fueled by fossil
fuels and hydrogen can be generated indefinitely, there are high expectations forthem as the ultimate in clean mobility forsolving many environmental problems.2)
The fuel cell used in FCVs is actually asmall generator that generates electricity
through an electrochemical reaction between hydrogen and the oxygen in the air.
A fuel cell consists of a membrane electrodeassembly (MEA) with electrocatalysts coated on both sides of a polymer electrolyte

membrane sandwiched between thin platescalled bipolar plates, which are composedof separate air and hydrogen flow channels.
Fig. 1 shows an overview of the set of structures called a cell. Hundreds of these cells
are stacked on top of each other to form
the actual fuel cell stack unit.3)
The initial fuel cell stack developed in2008 had a maximum output/volume of
1.4 kW/L (maximum output 90 kW/volume
64 L (108 kg)), but the latest model has amaximum output/volume of 3.1 kW/L (maximum output 114 kW/volume 37 L (56 kg)),
which is a 2.2-fold increase in volumetric
output density, and demonstrates the rapid
pace of miniaturization and performance
improvements.4)

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Higher performance of elements, suchas the MEA and bipolar plate, is a factor
in the improved output density, but the
bipolar plate must have three main features: (1) Complete separation of hydrogen and air flowing on the front and backsurfaces, (2) Fine and complex channel
shapes to increase the contact area withhydrogen and air, and (3) Thin cells to increase the overall unit density. However,in the conventional press, the thicknessof the plate is not uniform due to insufficient machining accuracy of the mold,resulting in extremely thin parts. This canlead to holes in the plate and the mixingof hydrogen and air.Therefore, the bipolar plate requires a high-precision moldthat can press the fine channel shape andplate thickness uniformly. This paper presents examples of using an ultra-precision
channel machining and compensation
method that was developed to improve
the performance of fuel cell stacks.
2. ULTRA-PRECISION MACHINING
CENTER UVMThis paper examines the use of ultra-precision machining center UVM to achieve
highprecision in fuel cell bipolar plates.
The UVM series is an ultra-precision machining center that incorporates the nanometer-order elemental technology6)
developed for the ULG series, which isused in the field of optical lenses, into
the realm of general-purpose machining.
Fig. 2 shows the four models in the UVM
series lineup. The UVM-450C series standard model has a table size of 450 mm x

450 mm. To handle large workpieces, theUVM-700C’s table work surface size has
been increased to 700 mm x 700 mm,
and the maximum loading weight has
been increased to 400 kg. The UVM-450D
is equipped with a thermostatic system
for strengthening the structure against
environmental fluctuations and an enhanced internal structure for vibration
control andhigh-precision positioning.
The UVM-700E (5AD) is a 5-axis modelthat provides a high degree of freedom
for large workpieces such as automobile
headlights. All UVM series models areequipped with Shibaura Machine’s aerostatic bearing spindle featuring a maximum speed of 60,000 min-1, and linear
motor control with a minimum setting
unit of 10 nm is used for all linear axes.

“”“ LINE AR AXISDRIVES OF THE
UVM SERIES ARE
EQUIPPED WITH
CORED LINE AR
MOTORS”

FIG. 2. UVM SERIES LINEUPNANOJIN 2021 WINTER

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3.

COMPONENT TECHNOLOGIES

3.1 AEROSTATIC BEARING SPINDLE

Shibaura Machine has been developing aerostatic bearing spindles for theirhigh-precision machine tools since the1970s. However, general machining centers
use ball bearing spindles, and even mostmachining centers that claim to be high precision use ball bearings. While it is true thatfor high-precision applications, the bearings
are designed to be ultra-lightly pressurized,
the rolling elements of the bearing are in
constant contact with the inner and outerrings, and so vibration, heat generation,
and wear are inevitable when the bearing
rotates. Therefore, compared to aerostatic
bearings, ball bearing spindles have thefollowing undesirable characteristics: (1)Inferior rotational accuracy, (2) Heat generation during high-speed rotation, and (3)“”“SHIBAURA MACHINE

HAS BEEN DEVELOPINGAEROSTATIC BE ARING
SPINDLES FOR THEIR HIGH-PRECISION MACHINETOOLS SINCE THE 1970S”

Inevitable deterioration over time.
The aerostatic bearings used in the UVM series have a structure where compressed air
is supplied between the rotating shaft andhousing to lift the spindle out of the bearing
and hold it in place by aerostatic pressure.
The air layer smooths out the accuracy error
components, making it possible to rotatesmoothly like exceeding the machining
accuracy of each component adversely affecting the rotational accuracy, such as theroundness and roughness of the rotating
shaft and bearings, for reducing the effectof vibrations. Fig. 3 shows a comparison of
the actual rotational accuracy measured
by a displacement sensor. The ball bearing
spindle in the figure on the left shows abnormal vibration errors due to the rolling
elements’ turning motion as they rotate,while the aerostatic bearing in the figureon the right shows no abnormal vibration
errors and rotates with a smooth path.

FIG. 3. COMPARISON OF ROTATIONAL ACCURACY

3.2 LINEAR MOTOR DRIVE CONTROLAll linear axis drives of the UVM series areequipped with cored linear motors. The
high-rigidity guiding mechanism has astructure that minimizes the degradation of
motion accuracy due to magnetic attractive
force, which is a concern with cored linear
motors, and has the advantage of allowing
the setting of high position loop gain anda control resolution of 0.5-nm scale feedback. As a result, the performance of thefeed system has been improved to a level
where steps of 10 nm can be accurately
controlled.
Fig. 4 shows the response waveform
for a 10-nm step feed measured at the sameactual machining point as the tool tip. The
waveform shows that positioning error at
the cutting edge was reduced, and accurate
and smooth reversing motion characteristics
were obtained with high response, which
improves the machined surface quality and

FIG. 4. 10-NM STEP RESPONSE AT MACHINING POINT

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minimizes manual finishing such as polishingand deburring in mold fabrication.7)
4.

MACHINING TECHNOLOGY

Two main evaluation criteria are used for accuracy in ultra-precision machining. These areform accuracy, which indicates the correctness of the form, and surface quality (roughness), which indicates the specularity of thesurface. In the field of ultra-precision milling,in addition to high-precision positioning of
the machine itself, high form accuracy has
been achieved by calculating the correct tool
path using 3D CAD/CAM with high calculation accuracy, and high surface quality has“”“ T H E M E AS U R E M E NT RESU LT S SHO W T HAT E V EN
A B R AN D NE W T O O L H AS
AN ER R O R O F A BO U T
4 M I CR O N FR O M T HEI D E AL R O U ND S HA P E ,WH I CH D I R E C T LY L E A DS
TO AN M A C HI NI NG
ER R OR . ”

been achieved by using a high-speed rotating
spindle to minimize chip formation and to reduce workpiece deformation. However, current machining technology is not adequate
for bipolar plate molds requiring high form
accuracy, and so we developed a machining
technology that corrects the accuracy error
component of ball end mills to achieve evenhigher accuracy.
4.1 HIGH-PRECISION TOOL SHAPE
DETECTOR FORMEYE

Tool measuring devices are installed in conventional machining centers to measure theposition and diameter of rotating tools formachining. The UVM series also uses a line

sensor type tool measuring instrument, which
has the capability to measure the contour of
the tool itself. However, in the conventional
methods for measuring the tool contour, there
is a large interior error on the measuring instrument side when the line sensor is switchedbetween horizontal and vertical, resulting in alarge step near the 45° angle of the tool, which
is a major barrier to achieving high-precision
correction machining. Since the sensor structure makes this error unavoidable, we studied replacement of the sensor with a method
capable of measuring the tool contour moreaccurately and found the imaging method tobe the most suitable. However, the imaging
method tends to result in more expensive
units and longer measurement times. There are
two reasons why imaging-type measurementtakes a long time: (1) Image processing of theentire screen takes time, and (2) Because thephase of the high-speed rotating tool cannot
be known when shooting, shooting must be
performed repeatedly until the photo with arequired phase is taken. For (2), because theaerostatic bearing is manufactured in-house,a rotation sensor for phase recognition can bebuilt into the spindle to identify the phase during high-speed rotation, making it possible tocomplete the measurement with a minimum
number of images. Furthermore, minimizing
the number of shots enables shorter times required for image processing, allowing for faster processing. Fig. 5 shows the appearance ofFormEye during measurement. FormEye canbe installed and maneuvered in the same way
as existing tool length measuring instruments,
and no special treatment is required. Fig. 6
shows the measurement results for the tool
contour. The measurement results show thateven a brand new tool has an error of about 4µm from the ideal round shape, which directly
leads to an machining error. Also, this measurement function enables step-by-step monitoring of the detailed progression of damage
to the tool edge due to wear or other factors
after machining, enabling accurate tool life
management.8)

FIG. 5. VIEW OF FORMEYE MEASUREMENT
FIG.6 TOOL CONTOUR MEASUREMENT BY FORMEYE
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FIG.7 BENEFITS FOR VECTOR CORRECTION OF TOOL PATH

4.2 TOOL PATH VECTOR CORRECTION
Even in ultra-precision milling, the machining process consists of (1) Modelcreation in 3D-CAD, (2) Machining
path generation in CAM, (3) Actualmachining, and (4) Measurement analysis. FormEye has made it possible toobtain accurate tool contour data,
but currently, no matter how highthe computational accuracy of 3D
CAD/CAM, only an ideal shape of aperfect circle can be defined for tools.
Therefore, if an error of 4 µm is foundin the actual tool contour, as shown in
Fig. 6, the error is directly transferredto the machined workpiece as a form
error component. If the tool protrudes
from the perfect circle, which is theideal shape, the machined workpiece
will be over-cut. However, if the tool
is receded from the perfect circle, themachined workpiece will have uncut
sections. In order to correct this error,
information is needed on which direction and how far to retract or advance.
Since FormEye provides informationon the unevenness of the tool contour, it is only necessary to identify
which position of the tool is acting
at each selected machining point on
the workpiece surface.
To solve this problem, we developed software that provides an error
correction function called “tool path
vector correction.” In tool path vector
correction, 3D CAD data is used to
identify each contact point of the tooland provide information on which direction to move the tool. Fig. 7 shows aschematic diagram of tool path vector

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correction. In the conventional process, a tool radius value is input tothe 3D model to calculate the NC data
for machining. If the result does notpass the subsequent analysis, it cantake nearly 100 hours to modify the
3D model and recalculate the NC databy inputting an optimum tool radiusvalue. Furthermore, if the machining
results are not satisfactory, this corrective machining routine must be
repeated several times, resulting in atremendous loss of production time.
In contrast, the process using tool
path vector correction automaticallycorrects the NC data coordinate values on the machine side based on thevalues measured by FormEye, making
it a “method of error correction not
returning to CAM” where 3D model
correction and NC data re-creation
are unnecessary. This enables significant reductions in loss of production
time from non-machining processes.

“”

W E DEV ELOP ED
SOF T W ARE T H AT
P ROV IDES AN ER R OR C OR R EC T ION
F U N C T ION C ALLED“T OOL PAT H V EC T OR
C OR R EC T ION .”FIG.7 BENEFITS FOR VECTOR CORRECTION OF TOOL PATH
FIG. 7. SCHEMATIC DIAGRAM OF TOOL PATH VECTOR CORRECTION

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5. MACHINING VERIFICATION
Machining verification of the bipolar plate
form was conducted with the aim of improving the form accuracy using FormEye andtool path vector correction. The 3D modeland cross-sectional view of the bipolar plate
form for machining verification are shown in
Fig. 8. The workpiece material was stainlesssteel for molds (HRC52), and the tool was acBN ball end mill (R 0.5 mm). Fig. 9 shows
the contour accuracy of the ball end milland the tool correction amount obtainedby FormEye’s tool shape measurement. The
correction amount calculated from the tool
contour is minimal around 0° at the tool
rotation center, and increases toward the
periphery, reaching a maximum of 2.5 µm
around 90°. Therefore, when machining without correction, the form accuracy will be 2.5+ α (effect of wear or disturbance) µm, andas the angle of the workpiece approaches
the 90° vertical wall, over-cutting due to tool
contour error is expected to occur. Using
this tool, a machining test was conductedto compare the correction effects with andwithout tool path vector correction. The form
accuracy of a cross section of the machined
surface was measured by a FormTalysurf
PGI850A (made by Taylor Hobson). Fig. 10shows the machining results without vector correction. The form accuracy is -3.2 to+0.2 µm (PV: 3.4 µm), which is a large error
from the design value and does not meetthe required accuracy. While the workpiecesurface is cut without error near the 0° angle,
excessive cutting is observed as the angle of
the workpiece surface approaches 90°. Fig.
11 shows the machining results with vector
correction. The results of machining with

vector correction show that the phenomenon of over-cutting that was seen without
vector correction has been improved, anda form with almost no error relative to thedesign form was obtained. The form accuracy was -0.6 to +0.7 µm (PV: 1.3 µm), whichis less than ±1 µm, which is required for bipolar plate molds.
6.

IREFERENCES
1) JAPAN AUTOMOBILE MANUFACTURERS ASSOCIATION, “JAPAN’S
AUTOMOBILE INDUSTRY 2020,” 30.
2) H.ONAKA, DEVELOPMENT OF FUEL CELL VEHICLES AT TOYOTA,HYDROGEN ENERGY SYSTEMS 34, 2, (2009) 10-17.
3) A.MIYAZAWA ET AL., DEVELOPMENT OF A NEW COMPACT
HIGH-POWER AND LOW-COST FUEL CELL STACK, SOCIETY OF AUTOMOTIVE ENGINEERS OF JAPAN 40, 5, (2009), 1267-72.
4) H.NAKAJI ET AL, DEVELOPMENT OF HIGH PERFORMANCE AND LOW
COST FUEL CELL STACKS, PRODUCTION AND TECHNOLOGY 68, 2,(2016), 72-75.

CONCLUSION

This paper describes one example of thedevelopment of machining technology forhigh-precision forming of bipolar plates
for fuel cell stacks. In addition to this case,many other industrial products are improving their performance at a remarkable pace,
and the component parts are becoming
significantly more precise and miniaturized.
Consequently, while more and more markets
will be requiring nanofabrication technology, there will also be more areas where conventional manufacturing processes cannot
be adapted, and so the production processitself needs to be examined beyond the existing framework. We will continue to identify
needs from new perspectives and strive toexpand the application scope of nanofabrication technology for manufacturing.

FIG. 8. MACHINING 3D MODEL

FIG.9 TOOL CORRECTION AMOUNT

5) HONDA MOTOR CO., LTD., CLARITY FUEL CELLHTTPS://WWW.HONDA.CO.JP/TECH/AUTO/CLARITY/FIVE_SEATER.
HTML (ACCESSED OCT.18.2021)
6) SHIBAURA MACHINE CO., LTD., ULC/ULG SERIES:HTTP://WWW.TOSHIBA-MACHINE.CO.JP/JP/PRODUCT/NANO/LINEUP/ULG_LG/INDEX.HTML (ACCESSED APR.12.2021)
7) A.AMANO, TECHNOLOGY TO IMPROVE THE ACCURACY AND EFFICIENCY OF MOLD MACHINING USING ULTRA-PRECISION MACHINING
CENTERS, MOLD TECHNOLOGY, FEBRUARY 2021.
8) Y.MUROFUSHI, IMPORTANCE OF ON-MACHINE TOOL SHAPE MEASUREMENT AND FORMEYE, A HIGH PRECISION TOOL SHAPE MEASURING INSTRUMENT, MOLD TECHNOLOGY, JUNE 2021.

FIG. 10. CRFIG. 10. CROSS-SECTIONAL FORM ACCURACYWITHOUT VECTOR CORRECTION

FIG. 11. CROSS-SECTIONAL FORM ACCURACY
WITH VECTOR CORRECTION

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EMO MILLAN
REVIEWC

hanging from Summer to Autumn early Octorber, Shibaura
Machine had a great opportunities to let the customer in Europe know
about who we are, what we do, how our
products work at EMO 2021 in Milano.
Since we changed our company namefrom Toshiba Machine to Shibaura Machine, it was the first time to present
our company and products in Europe.
In our booth, we displayed ultra-precision that integrates our excellent technology, samples machined by UVM series. You may also check our presented
samples in detail at EMO from the previous edition of the digital leaflet, named
NANOJIN_Autumn.

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EMO MILLAN
REVIEWC

reating something from nothing, it was so impressed that the booth had been completed rapidly. A lot of exhibitors and visitors from manyother countries came by Shibaura Machine’s booth andwere surprised by cutting hard mold with high form
accuracy and fine surface roughness. There were also
technical school students who have their fulfilled background in the certain field were interested in our samples like headlight.

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AND OFF THE COAST, A
NIGHT FISHING BOAT THAT
LIT LIGHTS FLUTTERS THE
FLAG OF A BIG CATCH
PRAYER AND WORKING ON
FISHING.

SURUGA BAY
WHEN THEY SKY IN THE SURUGA BAYTURNS ORANGE AT SUNSET.
MANY ANGLERS LINE THE COAST OFSURUGA BAY.
FISHES’ STARVING TIME IS A GREATCHANCE TIME FOR ANGLERS.

NUMAZU CITY, SHIZUOKA-KEN, IS A CITY
ON THE COAST OFSURUGA BAY, WHICH
IS THE DEEPEST BAY
IN JAPAN (2,500 M AT
THE DEEPEST PART).
SURUGA BAY IS
KNOWN AS A GOODFISHING AREA AND ISBLESSED WITH ABUNDANT FISH SPECIES.

THE PHOTO SHOWSA FISH NAMED MAHI-MAHI, A LARGECARNIVOROUS FISH
THAT IS DISTRIBUTEDIN THE WARM WATERS OF THE WORLDAND IS CAUGHT FOR
FOOD.
IN HAWAII, IT IS
KNOWN AS A SUPERCLASS SPIECES UNDER THE NAME OF
MAHI-MAHI.

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NANOJINGOTENBAThe wonderful panoramic view of Mt. Fuji from the windowof Gotemba factory is observable.

NANOJIN 2021 WINTER

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