FESTO a Perfect Fit

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Fully automated system for punching printingplates

In useReady-to-install handling system with linearmotor axis DGE-LM and compact vision systemSBOC-Q

Benefits• Optical position sensing of the register marks• Precision alignment of the printing plates on

an X/Y-axis table

Handling and assembly

trends in automation No. 11, 2007

A perfect fit

Precision placement: In Beil’s automatic plate punching press, linear axes

move the printing plate until the register marks are accurately positioned.

Securing, punching and forwarding does not take place until the vision sys-

tems give the green light.

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In order for the colours tomatch and the printed images tobe sharp, printing plates must lieexactly above one another. Toensure this precision right from themoment the plates are punched,Gunter Beil, owner of Beil Registri-ersysteme GmbH, decided todevelop an automated punchingsystem. Festo System Solutionswere on board right from the plan-ning phase through to implemen-tation.

Time is moneyGunter Beil went on to say, “Sinceour core competence is in the areaof precision mechanics, we wouldhave had to employ people withthe appropriate specialist skills todevelop an automatic plate punch-ing system. We didn’t want to loseany time as we wanted to presentthe machines just seven monthslater at the Ipex print and publish-ing exhibition. That's why wedecided to buy in the mechatroniccomponents.”

The order was placed with Festoaround seven months before thetrade fair. “We liked the technicalconcept and we valued the world-wide availability of spare partssince 90% of our machines areused abroad”, explains managingdirector Stefan Kreitczick. “If wehad needed to employ and trainour own staff first, we wouldn’thave had enough time”, addsArmin Baier, technical director ofthe company. “By accessing theknow-how of the system special-ists at Festo, we were also able totake advantage of the experienceof Festo’s automation experts forthe PLC, user interface, axis con-trollers and linear axes.”

Focus on platesA vacuum rotary table projectsabove the centre of the plate tableby just a few millimetres. Plate

after plate is either manuallyplaced on this table followingexposure or automatically sup-plied via a belt conveyor. Once the plate has been positioned atthe so-called trigger stops, the two compact cameras SBOC-Qcheck the positioning marks on the plates: a mark for checking theX and Y position and a fine line fordetecting rotation.

The cameras with a built-in elec-tronic evaluation unit enable posi-tional deviations to be quantifiedeven at this level and the correc-tion values to be forwarded to theFesto PLC PS1. It coordinates allmeasurement and drive-relatedcomponents and also controls the two linear motor axes with air bearings DGE-LM via the axescontroller (which together form an X/Y-axis table and support therotary table). In the case of strokesof up to 30 mm along the X and Yaxis, the two axes correct the posi-tion of the plate to 0.02 mm.

Schematic diagram of the new punching system developed by Beil: the punching special-ists bought the entire mechatronic subsystem for the prototypes ready to install fromFesto. For series production, Beil assembles the parts itself. Axes DGE-LM have no rotat-ing parts and no friction, which means they also have no frictional wear.

Beil attracted great interest at the Ipextrade fair in Birmingham (UK). The reason?Its new punching system. This system precisely aligns the register marks ofprinting plates – with the help of two com-pact cameras, an X/Y-axis table compris-ing new linear motor axes with air bear-ings and a spindle axis with servo motorfrom Festo.

24 Handling and assembly ... A perfect fit


The correction of the rotationangle is based on the result of themeasurement by the second cam-era and results in the actuation ofthe spindle axis DGE-SP via theservo motor. In the case of strokesof up to 50 mm, it can rotate therotary table via a lever of around40 cm by up to ±5 degrees withvery high resolution.

Before punching, the position ofthe plate is repeatedly checkeduntil the two cameras indicate aperfect alignment. “The PLC doesnot forward the signal to the Festovalve terminal CPX/MPA until thereference mark is perfectlyadhered to”, explains Armin Baier.“First, it actuates two clampingcylinders initially, followed by afurther five clamping cylinders.”Following punching, rodless pneu-matic drives DGC gently tip the

printing plates onto the platestacker. A standard cylinder DNCaligns them and places them onthe conveyor trolley.

Mechatronics from a single source“Our decision to develop themechatronic system as a ready-to-use unit together with Festo andalso buy in the components for theprototypes has enabled us to ben-efit from the experience of theleader in automation technology”,

says Günter Beil. “This was theonly way we could keep the time-to-market short enough to be ableto release the new system in timefor Ipex.”

A quick glance under the surface of the X/Y-axis table shows just how compact and flatthe mechatronic subsystem is.

Symbiosis of speed and precision:Linear motor axis DGE-LM

These days, repositioning and aligning of workpieceshas to be done with ever greater speed and precision.While up to now the toothed belt axis has been asso-ciated with speed and the spindle axis for precision,today the linear motor axis DGE-LM combines bothrequirements:

• 3 sizes: 30, 64, 120• Stroke lengths from 0 to 5000 mm• Feed force from 30 to 500 N• Speed 4 m/s• Repetition accuracy 1µm• Acceleration 90 m/s²

The other features are equally impressive:

Ultra-compact design• No external guide• Overall axis length = effective stroke + slide length

Maintenance-free operation• Air bearing with no wearing parts, as a result no

friction in the guide elements and no lubrication• Insensitive to dirt• No increase in temperature at high acceleration and

speeds

Plug and work• Integrated guide, displacement encoder and cable

connections• Precision mounting points via centring holes

Flexible control concept • Decentralised: simple actuation using Festo servo

axis controllers• Centralised: Festo controller or customer PLC

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The valve terminal CPX/MPA is positioned directly below the plate punching table. Itcommunicates with the higher-level drive controller via Profibus DP. In addition to actuat-ing the punching cylinders pneumatically, the valve terminal also registers the sensors.

Compressed air preparation is performed by an MS series service unit. It supplies thepneumatic cylinders and the air bearing system of the linear motor axes DGE-LM.

Festo components

at Beil

Spindle axis DGE-SP

Linear motor axisDGE-LM

Compact visionsystem SBOC-Q

Display and controlunit FED-90

Electrical terminalCPX with valve ter-minal MPA

MS seriesservice unit

Compact cylinderADVU

Beil Registersysteme GmbH

Products Register systems for the printingindustry: register punches, platebenders, accessories for the CTPpre-stage and printing

Contact 93326 [email protected]

is 1107Compact vision system SBOC-Q

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FESTO a Perfect Fit