At thecamera-controlledelectrodemillingdevice:
LeifWinberg, Plant Engineer forResistanceWeldingat
Volvo inOlofström (left) andLeif Lindahl,BusinessDevelopmentManagerAutomotivewithFestoSweden.
Timesavings:
Thenew tipdresserssignificantly
reduce cycle timeswheremultiplewelding
robotsare inuse.
Tipdresser for articulated-arm robots:
On the right the twoholes for
electrodemilling, andon the left the compact housingwith thevision
systemwhichprovides thedata for repositioning theelectrodes.
For staticweldinggunsystems:
A fast andprecisepivot arm
brings theelectrodemillingdevice, theso called tipdresser,
to theelectrodesafter 150spotweldshavebeen completed.
Joint development
“In recent yearswehave foundsolutions
whichhaveenabledus tocut thecycle
times for electrodemillingbywell over
half,”continuesWinberg. “There isalsoa
gain insafety, sinceplantoperatorsno
longerhave toenter the robot cellsafter
milling inorder toadjust theelectrodes to
thecorrectposition for thespotwelds,”
addsLeif Lindahl,BusinessDevelopment
ManagerAutomotivewithFestoSweden.
For staticweldingguns, Festodeveloped
a customisedpivot armexactlyasper
thespecificationsofVolvoandABBwhich
brings theelectrodemillingdevice, theso
called tipdresser, to theelectrodesafter
150spotweldshavebeen completed.
Thepivot arm ispreciselypositionedby
Festoelectric cylindersDNCE. Thanks to
freelyprogrammablepositions, these
electric cylindersareflexible in termsof
motionandaccelerategently. The
complete ready-to-install electrical
packagesuppliedby Festo includes
steppermotor EMMSandmotor
controllersCMMS. Themotor controllers
aresafely integrated inacontrol cabinet
with theautomationplatformCPX.The
CPXcommunicateswith themotor
controllersandwith themaster control
system for the robot installationvia
Profinet.
Electrodemilling controlledby
visionsystem
Mobile tipdressersarenot necessary for
theweldinggunson theABBarticulated
robots. These robots can feed their
electrodes themselves to theelectrode
millingdeviceafter 150spotwelds. This
freedomofmovement of theweldingguns
opens completelynewhorizons. Inafirst
step, thearticulated robot brings the
weldinggun to the tipdresser. This then
mills theelectrodes. In thenext step, the
robot swings itselectrodes in front of the
lensof the FestovisionsystemSBO.
