 |
 |
|
Shaftless technology now a realityWith the launch of a new higfh speed communications option for its variable speed drives, Eurotherm Drives has enabled OEMs and machinery users to finally realise the benefits of shaftless technology in complex machine systems without compromising synchronisation accuracy. With all industry sectors facing increased competition, often on a global scale, boosting productivity has become a key issue. Manufacturers are looking to run machines faster, reduce wastage levels, and increase flexibility by making it easier to change machinery settings for different product runs. The limiting factor in achieving this in most machine designs tends to be the mechanical components, and the last few years has seen the steady replacement of mechanical cams, linkages, and the like, with electronic motion control systems. However, in industries such as printing and paper manufacture, where the machinery is huge and complex, and assured synchronisation between key aspects of the machine often down its entire length is an absolute priority, there has been no readily available electronic alternative to the line shaft. The communications simply are not fast enough to ensure accurate synchronisation along the machine. To provide a solution, Eurotherm Drives has enhanced the communications options within its drives ranges to include Firewire, providing exceptionally high speed networking via the company's fibre-optic based LINK system. The result is a drive system specifically designed for ultra-high performance phase and registration control applications including shaftless printing and paper manufacture. Flexible controlLINK provides a complete distributed control system, enabling a highly flexible control strategy to be implemented. LINK includes configurable analogue, digital and serial I/O modules that can be distributed on machinery to minimise signal and control wiring. There are no expensive I/O adapters or racks to worry about, and each module has its own application memory and processor to execute application software locally. Removing the need for a separate motion control station or PLC, LINK provides full distributed control, programmable from a single point. Each LINK component utilises high speed peer-to-peer communications over a real-time fibre optic network, eliminating the signal and control wiring between drives, operator stations and system I/O. The new Firewire option modules for the drives products in the Eurotherm Drives range facilitates data transfer at up to 400Mbps over the fibre optic cable, and provides deterministic communications. The system enables major mechanical linkages to be eliminated in machine designs or removed in machinery upgrades in favour of an all-electronic solution that is far easier to set-up and maintain. "The ability to independently drive sections of a machine without a common lineshaft offers great advantages in terms of accuracy, set-up time, wastage and maintenance," says Eurotherm Drives sales director Mark Hartley. "By employing non-proprietary standard Firewire technology, the drives can communicate up to 40 times faster than other shaftless systems on the market." In a typical shaftless system, the enhanced drives and their associated standard AC induction or permanent magnet motors replace mechanical elements such as line shafts and gearboxes, and are networked via Firewire to LINK. Accurate synchronisationThe high speed Firewire communications ensures accurate synchronisation between the drives along the length of the machine, whilst the drives themselves offer positional accuracy of 4 million parts per revolution, achieved using SinCos encoders and inbuilt 32-bit digital signal processors. A futher advantage of the fibre-optic network is its inherent immunity to noise interference. Providing highly robust, flexible, efficient and dynamic control of machinery, the LINK system is designed to be extremely easy to install and commission, whether on new machinery or as part of an upgrade project. Instead of working around a single line shaft, the concept allows machinery to be broken down into islands of control without compromising synchronisation between the various aspects of the machine. Indeed, the enhanced electronic control system provides improved synchronisation, quickly showing just big a limiting factor the mechanical system can be in boosting productivity. In general, machines which are built around shaftless technology are easier to run. And because the machines are more controllable, errors are reduced and so productivity can be improved. Where line shaft arrangements are notoriously temperamental, the electronic control system stays locked to the set parameters, resulting in a far more consistent end product. The electronic control system also significantly reduces the time taken to change machinery settings for different product runs, again boosting productivity. "The system will provide real benefits for OEMs in a whole host of applications where there has been a traditional reliance on shaft technology to provide synchronisation along complex machinery," says Hartley. "Shaftless printing is a perfect example of the increase in flexibility and the cost savings that the technology can deliver. OEMs can now build colour towers individually, saving on time and space, and it is easy to add extra colour stations to an existing system. "Set-up time is vastly reduced, and maintenance is simplified thanks to the elimination of mechanical wear," he continues. "Also, removing mechanical parts reduces noise levels. Printers will also find operational benefits, with improved control ensuring less wastage of paper. And paper manufacturers will enjoy similar benefits, being able to run machines at higher speeds and at the same time achieve a more consistent quality of the finished product. Overall the technology can deliver vast cost savings and a very quick return on investment."
|
Home Magazine Directory Show Reviews Links Media Guide
© Copyright 2004 Magpye Publishing Ltd.