Low-wear roller energy chains for loading gantries in the automotive industry

• What was needed: Profile roller energy chain P4.32 with autoglide system and aluminium guide trough, supplied as a pre-assembled readychain® system
• Requirements: high dynamics at travel speeds of 6 m/s and accelerations of 6 m/s2; wear resistance; high availability; noise minimisation
• Industry: automotive industry, machine tools
• Success for the customer: the roller energy chains easily cope with the high dynamics of the system in continuous operation; the roller system is wear-resistant, reliable, smooth-running and requires 57% less drive power compared to sliding chains;v the pre-assembled readychain® system was able to minimise assembly time and costs

The product range of GROB-Werke GmbH & Co. KG includes flexible manufacturing systems for the automotive industry. These include machining centres, special machines and their automation.
The company has developed a new linear gantry, also known as a translator, which was presented with great success at the EMO.
The new linear gantry, or translator, is much more compact and smaller than the company's previous solutions. The height of the X-beam above the hall floor is just under 3.20 metres.
A new development is the vertical suspension of the carriage, which can carry loads of up to 80 kg, and the loading arm on large skate wheels below the X-beam. The already proven technology of the loading arm in parallel kinematics has also been further improved. The gripper can be supplemented by a swivelling axis in the A or C direction. By reducing the moving masses, significantly higher travelling speeds and acceleration values are achieved. With a travelling length of up to 40 m, the speed is 6 m/s and the acceleration 6 m/s2. Speed and acceleration were thus twice as fast as with the previous model. The significantly improved dynamics of the linear gantry enable the loading of interlinked single and twin-spindle machines with a single gripper.
A complete production line consists on the one hand of the linear gantry and on the other hand of single and twin-spindle machining centres for the workpieces.
Due to the high dynamics of the gantry, questions quickly arose for those responsible regarding the appropriate energy supply system. In addition to other requirements such as high wear resistance and a long service life, it was necessary for reasons of occupational safety that the sum of all noises should be relatively low at the same time.

In the preliminary tests, magnetic chains and plastic energy chains were pitted against each other. The decision was clear: internal analyses showed, among other things, that magnetic chains neither meet the requirements for smooth running nor can they withstand the high speeds in the long term. The linear gantries usually run six days a week in three-shift operation, and machine or system downtimes are not permitted. Low-maintenance roller energy supply systems from the P4 system are therefore used in the linear gantry. The special design of the rollers and chain links enables particularly quiet running. The chain is also suitable for high travelling speeds, long travel distances and high filling weights. The staggered rolling of the upper and lower run further increases the service life of the chain. It is also particularly abrasion-resistant. The roller chain achieves particularly smooth and vibration-free running. Cable-friendly 'Auto-Glide' crossbars made from tribologically optimised plastic and aluminium channels from the modular system guide the energy chain safely. There is also a silencer profile in the trough, which further minimises noise development.
Compared to sliding friction, rolling friction is generally 75 % lower. The resulting reduction in drive power of up to 57 % means more energy-efficient work processes.
The energy supply system was supplied as a pre-assembled, ready-to-connect® system and can be easily installed via "plug and play".
Plastic energy supply systems are also used for the horizontal sliding changer in the linear gantry, which replaces the swivelling changer during loading and unloading. They ensure the necessary machine and system availability that GROB-Werke guarantees its customers all over the world.