Very high demands are made on workpiece manufacture in model and mould making, and since customers’ space requirements are generally tight, tailor-made concepts are often required. Robust energy chains from igus UK are suitable for such applications and are guiding large vacuum hoses safely.
Trima Triebeser Maschinenbau GmbH manufactures bespoke CNC machining centres for machining wood, plastic and metals, for the production of windows and staircases, interiors, doors, furniture, arc work, engravings, toys, and much more. One of the company’s main focuses is on the development of machining centres for model and mould making, which are mainly used for applications with high-precision workpiece processing in individual and series production. Despite their complex design, standard parts are usually used in these customer-specific machines. Heavy duty plastic energy chains supplied by igus UK are critical for cable guidance, and both companies have been working together successfully for years.
Michael Schell, Chief Designer at Trima Triebeser Maschinenbau GmbH says: “Since we do not make off-the-shelf products and do not have any fixed assemblies, expert advice during the design phase is particularly important to us. In special-purpose machine construction it is absolutely necessary that the machines run smoothly under all conditions first time. This also applies to the components used, such as the energy chains.”
Machining centres for model and mould making are available with 3 or 5-axis technology, and in the future the main focus will be on 5-axis technology, which offers more flexibility. A 5-axis machine with a cardan head, currently being used for a foundry pattern-making project, has been tailor made for limited work space. The machine reaches every corner of the workpiece collision free.
Since the machining of small and tiny contours takes a very long time, the machine runs 24 hours a day, and during the night it runs independently without a machine operator on site. The requirements on the components used are therefore appropriately high, and the drives have to work reliably and the spindles must not heat up. There is also a marking system on the 5-axis head which is used for nesting.
The machining centre has an overall height of 3m and a component or passage height of 500mm. The distance travelled is 4.1m in the x-axis, 2.6m in the y-axis and 1m in the z-axis. During this movement, speeds of up to 1m/s and accelerations of 5m/s² are achieved. Vacuum-clamping jigs are used on the machine table, guaranteeing flexibility necessary during part machining. Woodworking is involved in this application, which means extraction plays a very important role.
Michael explains: “It is not wood chips that are the problem in this environment, it is wood dust. It must never be allowed to ignite.” A complete casing would be the safest – but also the most expensive – option. “For cost reasons, we decided in favour of an extraction hose,” he adds. To make sure the hose is guided safely and cleanly, it has been enclosed in a special energy chain from igus. The large-volume extraction hose has a length of more than 6m and a diameter of 0.3m. Michael Schell explains: “The large diameter meant that safe guidance inside a ‘normal’ energy chain was not possible. We also had to consider the limited space the customer had available. For this reason, we visited the site together with our igus contact to look for a solution, and found one very quickly.”
From igus’ range of over 70,000 energy chain products, an ‘extender crossbar’ version of the E4/light series was chosen to gently and safely guide the hose. The clamps are mounted directly on the sides and guarantee optimum hose and cable guidance. The crossbars are rigid, and they guarantee safe guiding over the whole travel distance even under heavy loads, without additional design elements being required.
The safe guidance of the exhaust hose inside the energy chain means constant extraction is possible in every travel position. The machine table can also be accessed from above, which means a crane can be used for loading and unloading.
The light version of the E4 energy chain also provides a weight advantage. The sides and crossbars are very sturdy but slimmer than the standard version, which means more space inside and reduces costs. The E4/light energy chain system is particularly suitable for shorter travels, hanging and smaller, standing designs.
A total of four energy chains are used in the machining centre: universal chain E4.1 for the x-axis, series E2/000 and the E4/light clamp version for the y-axis, as well as an E2/000 energy chain for the z-axis. E4.1 can be implemented in almost any application and can be opened on both sides. Design features include a tongue-and-groove design for high stability, high shear forces on long travels and large unsupported lengths. In addition, outer and inner brackets ensure quick installation. The chain is dirt repellent and has a smooth wear-resistant surface.
One special design feature on the y-axis is that the energy chain carrying electrical cables runs inside the extender chain. This is so sturdy that it can safely bear the weight of the E2/000 cable carrier, as well as the bulky exhaust hose. Michael Schell adds: “And we save a lot of space, too.”
Trima always uses separators from igus in all its energy chains. Thanks to their rounded contours, these components ensure a long service life for the cables in demanding operational conditions and always keep them in line. The guided cables can neither slip nor become tangled.
For further information about igus energy chains visit www.igus.co.uk.