Highperformanceat theheart of fuel cells:
Bipolar platesunmachined (left) andmachined.
Direct energy
Discoveredmore than170yearsago, thedevelopment of fuel
cellswas formanyyearsovershadowedby combustionengines.
Although they facilitated themoon landingasanemission-free
energysource in the1960s, their potentialwasonlybrought to
theattentionof thewider publicas the climate changedebate
intensified. Unlike thermal engines, fuel cellsgenerateelectrical
energydirectly fromchemical energy.Theydonotneed tounder-
go thermal processesandmechanicalworkfirst.Without the
complexconversion intoheatandpower, fuel cellsachieveahigh
degreeof efficiency Individual cells consist of twoelectrodes
andasemi-permeablemembrane, also referred toasabipolar
plate. Electrical energy iscreated through theexchangeof hydro-
genandoxygenelectronsandprotonsbetween twoelectrodes.
P+KMaschinen- und
AnlagenbauGmbH
Schlagbaumer Straße92a
42653Solingen
Germany
Areaof business:
Design, development andproduc-
tionofmechanical andelectrical
systems, special purposemachinery,
manufacturingequipment, fixture
construction, assemblysystems,
testingstationsand leak testers
“Movingandpositioningwith the
electric cylinder EPCO issmooth,
enablingus tooperate thesystem
withahigh cycle rate.”
Peter Kronenberg, GeneralManager of P+KMaschinen- undAnlagenbauGmbH
This issupportedbybright fieldanddark
field illumination. All typesof surface
defects canbe identifiedwith thehelpof
varying lighting conditions. In thesub
sequent station, theplatesare turnedby
180degreesso that asurface inspection
of theunderside, alsoknownas theflow
fieldside, canbe carriedout. The testing
stationdetermines the thicknessof the
bipolar platesat a total of ninepoints.
Themonitor positionedabove thestation
shows thecurrent imageof thebipolar
plateandprovidesuser-friendly, visual-
isedaccess to themeasurementdata. The
comparisonwith the imagedatashows
whether thebipolar platesareof suffi-
cientlygoodquality. Defectivepartsare
ejected from theprocess,while thesystem
transports thegoodparts toa transfer
station.Here, anelectrichandlingunit on
theZ-axisplaces them inamagazine.
Electric cylindersEPCOensure that they
are transportedgently to thestorage
position. Thanks to their technologically
sophisticatedend-position cushioning, as
well as their ball screwandnon-rotating,
plain-bearingpiston rod, theyprevent
event thesmallest amount of damage to
thebipolar plates in themagazine.
Continuous transport
Thefluidmovement aidedbyelectric
cylinder EPCO facilitates continuous
circulationof the16workpiece carriers
in thesystem. This is theonlywayshort
cycle timesof around four seconds can
beachieved. There isno time tostop
thesystem for imageacquisition in the
measurement stations. Positioning
tasksare carriedout inparallelwith the
measurements. These could lead toshock
andvibrationwhenusing conventional
cylinders, negatively influencing the
measurement resultsof the cameras.
Thisproblemdoesn’t occurwithsmooth-
runningelectric cylindersEPCO. The cylin-
dersalsooffer theadvantageof extremely
easy teach-inand reduce the costsassoci-
atedwith commissioningandproduct
changeover.
IO-Link isusedasaplant-widebussystem,
from themaster toall sensorsanddrives.
All thesystemperipherals can thusbe
connectedquicklyandeasily, significantly
reducing theamountof timespentonpro-
gramming. Thenew testing facility from
P+Kshowshow the continuousdevelop-
ment of processautomation components
insmall steps can contribute toground-
breaking technologies.
Turning theplatesby90or 180degrees–
this isdone
byapneumatic semi-rotarydriveDRQDmountedon the
Z-axiswithin the three-dimensional gantry instation1.
Avalve terminalVTUG,
connected to themaster
controller via IO-Link, controlsall thepneumatic
actuators in thesystem.
Storingbipolar plates
In thishandlingsystem, thestepper
motorsof electric cylinder EPCOand toothedbelt axisELGR
areactuatedbyservo controller CMMO-ST.
1.2014
trends inautomation
Synergies
38
–
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