Phil Burge, communications manager at SKF, looks at the latest developments in linear motion technology and the benefits it can offer to a range of applications
OEMs and machine builders have used electromechanical linear motion technology for many years as a primary method of moving, positioning, clamping and handling tool pieces, components and finished products.
This technology is also suitable for a wide variety of different environments – including laser machining parts and electronic production lines – where high performance, quiet running and space efficient units are required.
This widespread use across many sectors of industry is due to a number of factors, not least the rapid development of the technology over the past decade. This has resulted in a generation of products that can offer a viable alternative to hydraulic and pneumatic solutions in particularly demanding operating conditions.
These devices, for example, are capable of extremely high levels of performance over long, low maintenance operating lives, with the ability to position even heavy loads with submicron levels of precision. This is offering companies the opportunity to realise considerable improvements in efficiency and, consequently, increase profits. Furthermore, requiring little maintenance or manual intervention, the products are allowing the necessary resources and operating costs to be cut significantly.
With the engineering industry coming under increasing scrutiny to operate in an environmentally sustainable manner, the benefits of electromechanical solutions over the traditional fluid power alternatives are growing and look set to continue to do so as the technology evolves. By comparison with hydraulic and pneumatic pumps and motors, electromechanical linear motion systems consume a significantly lower amount of energy. In addition, the risk of contamination through the leakage of oil, whether directly or as particles in compressed air, is also eliminated through the use of electrical technology.
Meeting application demands
With more and more sectors looking to take up this technology, even stronger and more robust systems are being launched. There is now a wide range of motion technologies available – including linear bearings, profile guide rails, precision rail guides and roller screws – meaning that the right solution can be found to meet the requirements of any application in terms of load bearing capacity and levels of positioning accuracy and repeatability. Moreover, these robust positioning systems can operate in a wide variety of environments, such as on-board aircraft or inside hospitals, where space and weight saving is at a premium and almost silent running is essential.
The technology is also making its name in new global markets, particularly in developing regions where businesses are looking for solutions that allow them to meet the growing regulations in relation to energy use and environmental impact.
Complete assembly development
Traditionally, linear guides were supplied as standalone units that needed to be combined with a driving element, typically in the form of a ballscrew or roller screw, and engineered into positioning systems, often with specially developed ancillary guide mechanisms. However, this process could be relatively time consuming and expensive.
In answer to this, machine builders now often work more closely with the manufacturers of linear motion systems to develop complete assemblies or sub-assemblies that are pre-configured and tested off-line, minimising machine build time and costs. Perhaps as importantly, this process is also helping to increase still further the performance and functionality of linear motion devices and, by default, the performance and functionality of machine systems. Innovative new devices have also been introduced, such as telescopic pillars and rotary actuators, expanding the uses of the technology still further, with control units also having been developed to make automating systems simpler still.
Dependent on the requirements of the application, manufacturers can incorporate feedback devices into these sub-assemblies to establish speed and position, as well as special configurations to support structural loading. Some sub-systems can be developed to accommodate operating conditions and environments, while systems are also available to suit more universal specifications.
Over and above sub-assemblies, some manufacturers are now providing fully integrated mechatronic systems, offering a complete package that has been developed to respond independently to inputs and offer real-time feedback. This solution can help machine builders when designing systems for almost any industry – from factory equipment, automotive manufacturing devices and off-road vehicles through to surgical and food manufacturing equipment.
Catering for the future
Even over the past decade, electromechanical control technology has undergone a considerable progression and is now well placed to meet industry demands.
As more and more companies adopt these devices to combat the increasing pressure to reduce energy consumption and minimise their environmental impact, while simultaneously improving their own business performance, the benefits of electromechanical technology are likely to drive the development still further, with even more efficient solutions to cater for the businesses of the future.