Industrial Technology - Linked-in Industrial Technology - Twitter Industrial Technology - News Feed
Latest Issue
Diary and Events

Advanced Engineering 2021

NEC Birmingham(B40 1NT)

03/11/2021 - 04/11/2021

Join us in our 12th and most important edition to date, as we invite engineers and management from all (more)

Intelligent drives at the heart of printing machinery

Intelligent drives at the heart of printing machinery Continuing our Made in Britain series, we look at how Southampton based Rotary Logic Systems has improved the performance its printing, converting and finishing machines with intelligent variable speed drives.

Every system made by Rotary Logic Systems is bespoke, whether it is high precision security foiling for anti-counterfeit applications, specialised in-line, high speed flexographic or gravure printing processes, or sophisticated machinery for the medical industry. One factor is common throughout this wide range of high performance machinery - drives, servo-drives and servo-motors from Control Techniques.

Rotary Logic Systems, based near Southampton, supplies both standalone machines and modules to integrate into all applications in the converting and finishing industries. "We need drives that are flexible in operation, straightforward to program and with very fast response - that's why we use mainly Digitax ST Plus servo-drives from Control Techniques," says Alan Chandler, director of Rotary Logic Systems. "The speed of response we need on many modules just cannot be achieved with external PLCs. The response times are much faster, because the drives' processors are within the drives themselves."

A typical project is a series of six lines for a manufacturer in India. Each is a multi-stage anti-counterfeit line for packaging incorporating high precision application of a hot-foil hologram. The lines have web widths of 1320mm, and each comprises unwind and in-feed, foiling, flying head die-cutting, flexographic printing, out-feed and rewind. A total of 30 drives from Control Techniques are on each line: 9kW Unidrive SP drives control the unwind and wind operations, whilst Digitax ST Plus servo-drives twinned with Unimotor FM motors control the feeds and all other processes.

A variety of SM-Application modules are employed on many of the drives - including SM-Register, SM-Ethernet, SM-I/O - and the whole line is co-ordinated using Control Techniques' own high speed network, CT-Net, with the web material drive acting as the 'Master'. There are two points of registration - one to the pre-printed material and one to the applied product. A repeatable accuracy of ±0.1mm is required for the foiling process - and this is achieved with a line speed of 80m/minute.

"With changes in the needs of our client, we had to devise a system that maintains accuracy of application on an inconsistent substrate," explains Chandler. "This has been achieved within the software - Control Techniques has worked alongside us for two years to help develop this - and we believe it is unique in the finishing market." The software compensates for errors for every image, keeping each within tolerance.

Rotary Logic Systems has been a major user of Control Techniques' drives, servo-drives and motors for some six years, buying many hundreds each year. "We particularly like the Digitax ST series of servos," says Chandler, "not just because of their flexibility and performance, but also because of their compact size. Equally the compact size of the Unimotors is critical on many lines, including the lines supplied recently to India.  But, above all, it is our relationship with Control Techniques' engineering and software departments that has been so important over the last few years. As a company they are prepared to be flexible and provide excellent support."
Download pdf

Other News from Control Techniques Ltd

I/O modules enable process control with the need for a separate PLC

Latest news about Drives and motion control systems

Additional Information
Text styles