Beckum-based intralogistics specialist BEUMER Group has developed a new, highly efficient friction drive system for high-performance sorters as an economical alternative to the asynchronous linear motor drives used previously.
BEUMER OptiDrive, the new friction wheel drive system has been innovatively engineered so that the contact pressure of the drive wheel is automatically set depending on the required drive force for driving as well as for braking, boosting efficiency and enhancing the service life of the drive wheels.
According to the Federal Environmental Agency, electrical drives in industrial and commercial applications consume almost two-fifths of all electricity in Germany. Therefore, optimised solutions offer users enormous potential for reducing operating costs and conserving resources.
First introduced in 2010 for the smaller BS7 high-performance sorter, the intralogistics specialist has now also implemented the OptiDrive technology for larger models from the BS25 to the BS60, with mechanically or electrically operated load-bearing elements.
According to Heino Heitplatz, Team Leader Research & Development and Deputy Head of Development at BEUMER, they used the OptiDrive technology to replace the existing double comb asynchronous linear motor drives in these models to increase efficiency, reduce procurement costs, and ensure high availability with minimum maintenance and repair costs.
BEUMER high-performance sorters are used for sorting and picking a variety of items such as mail, textiles, mail order products, foods or baggage.
In the BEUMER OptiDrive, the contact pressure with which the drive wheel is pressed against the movable friction blade of the circulating carriage assembly is automatically adjusted proportionally to the required driving power, allowing the drive to always automatically operate at the optimal operating point. It not only allows for safe and slip-free starting up of the sorter from a standstill, but also improves efficiency in the predominant partial load range, while also prolonging the service life of the drive wheels. The energy consumption has consequently been reduced by up to 80 percent compared to the previously used asynchronous linear motor drive. The new OptiDrive BS25/55 enables companies to achieve effective efficiencies of up to 85 percent.
More efficiency, less wear
The new drive system’s double-acting proportional contact pressure works in both directions of action, i.e., when accelerating and braking. This enables the new OptiDrive to act as a holding brake. Unlike single sided linear motor drives, this solution does not cause attraction forces between the drive and the carriage, reducing the load on the carriage as well as wear. The drive also lines itself up with the carriage, eliminating the need for the user to adjust the system.
With this drive method, each carriage has a blade on the underside that acts as a friction blade. The blade is clamped between the friction wheel and an opposite pressure roller and pushed forward. The drive power transitions to the carriage system via this blade. The drive unit is connected to the sorter frame by means of a centre of rotation. This ‘floating’ bearing prevents transverse forces from the drive unit transferring to the carriage at all times.
Specially adapted for optimal operation
The OptiDrive is powered by a modern, highly-efficient gearless synchronous servomotor. The drive wheel is mounted directly on the motor shaft. The direct drive also allows for a very compact design and has its own controller, which is installed locally in the field. The controllers are in close proximity to the drive. The individual drive controllers use Profinet to communicate with the sorter controller. The Profinet installation is daisy-chained, as is the power supply to the drives, reducing the required cable length and the installation overhead. A special control algorithm ensures that all the drives apply the same propulsion power to the carriage system at any given time.
The BEUMER OptiDrive BS25/55 is designed for a permanent propulsion power of 600 Newton, and a short-term propulsion power of 1,000 Newton (for acceleration and braking processes) as well as for sorter speeds of up to 3.2 metres per second. The system is monitored by numerous diagnostics systems with any malfunctions indicated to the operator in good time. The user can also maintain the drive system remotely.
Placing great emphasis on sustainability
The BEUMER Sustainability Index (BSI) is a validation system, which is used to systematically and continuously measure sustainability in terms of economy, ecology and social responsibility, both on new machines and existing solutions. The Group has committed to evaluating its products comprehensively on three levels: economy, ecology and social responsibility. The BSI is a points system that rates products on these three levels. Economic performance, market presence, financial opportunities and risks are well-known parameters. Products only become economically sustainable when they, and their corresponding production processes, are tailored to long-term customer use.
This development has allowed BEUMER to reduce the production costs compared to other drives. This also has a positive effect on the customer's investment costs. The lower energy consumption and the more wear-resistant working method also significantly reduce operating costs. The higher efficiency translates into superior results in terms of both economic and ecological sustainability. Large amounts of copper were saved in the production of the motors and supply cables. The double-acting proportional contact pressure means shorter braking distances of the carriage in an emergency stop, which improves employee safety. Since this drive system does not need fans, the operating noise has also been reduced, creating a more pleasant working atmosphere.