The development of enhanced and improved clamping devices plays an important role in efficient production. In order to configure small batch set-ups as cost-effectively as possible and to maintain or increase competitiveness, there are additional adjustments that can be made. One of these is the integration of an automation system designed for innovative clamping systems. This facilitates higher productivity as well as streamlined management of equipment and workpieces by utilizing machines effectively and keeping distances short.
"Small batch and toll manufacturers are driven by one key issue: how to decouple the work tasks of operating personnel from machine operation times," said a Liebherr spokesperson. "Decoupling a machine's set-up and operation from the cycle time required for machining a workpiece offers major potential for increasing utilization and reducing unit costs in the long term. Long set-up times, especially for small batches, considerably reduce productivity; it is especially costly if the employee needs more time to set up than the machine needs for machining. It is here that automation systems come into play.
"Liebherr's Rotary Loading System (RLS) offers cost-effective entry into high-efficiency production with one or two machines - delivering utilization of more than 90%.
"Using the RLS to extend a machine's running time makes investing in an additional machine completely unnecessary in certain cases. This solution is clearly more effective than marginal increases in productivity that could result, for example, from optimizing CNC programs or the tools of machines that are manually fed or partly automated. One or two machining centers can be docked to the system."
For batch size 1 and above, the RLS offers efficiency potential. The operator can use the machine's running time to perform other production tasks; set-up costs thus do not enter into the machine costs/hour equation. The system is designed for workpiece weights of up to 800 kilograms (RLS 800) or 1,500 kilograms (RLS 1500) and dimensions up to 1,300 millimeters.
"The formula is simple," said Stefan Jehle, Automation Systems Area Sales Manager at Liebherr-Verzahntechnik. "Optimum machine utilization and reduced staffing requirements result in decreased unit costs - up to 20%. So as a rule, the investment pays for itself in less than two years. Moreover, the system improves delivery capability and facilitates rapid, flexible responses to changes in customer demand."
The RLS is designed as a cost-effective, entry-level solution for users with very small batch sizes (batch size 1 and above) or small batch manufacturers. "These are, for example, toll manufacturers with 20 to 30 employees, or tool and die makers who manufacture individual components with very long running and set-up times, as well as very substantial cutting capacity," said Stefan Sattelmayer from Liebherr-Verzahntechnik's sales and marketing department.
This technology is also designed to integrate existing machinery. The system can be adapted to accommodate older machines at relatively low cost. Liebherr tests this in advance, based on the existing production and machine layout. There are usually several small mechanical adjustments needed to establish accessibility. Machining parameters like CNC programs and tool data remain in the normal machine environment and are linked to the RLS via a Profibus interface.
"Given its compact dimensions and high storage density, Liebherr's circular storage solution is also suitable for end users who cannot accommodate a linear system," said the spokesperson. "The system's rack columns are of modular design, meaning that the customer's specific requirements can also be met. Up to 24 storage locations on a minimal footprint offer sufficient work-in-progress to by-pass an entire third shift.
"Customers who may have only one production application benefit from this entry-level solution when, for example, not all their production is to be geared towards automation."
"The RLS retains its flexibility even after initial start-up. The optional Rotary Storage Tower (RST), which can be added later and is unique in the market, raises the number of storage locations on the smallest footprint," said Sattelmayer. "This flexibility allows the system to be easily upgraded for more storage locations or a second machine. The tower creates space for up to 18 additional storage locations with only a minimally higher space requirement. The important factor of future reliability is therefore added to the flexibility of the basic design - an issue where similar systems on the market have their limitations." All components are already pre-configured to integrate any number of machine contours. If needed, the users can retrofit up to two storage towers. The form of the storage module permits the docking of a second machine in various positions - depending on at which location space is available.
The modular system consists of four basic elements:
- Rack module
- Set-up module
- Lift module
- Optional: Rotary Storage Tower.
The system design enables the user to easily access the automation engineering. In conjunction with the clearly structured operator interface, the windows around the facility allow an overview of the as-is status in and around the automation engineering. The integrated set-up station is located next to the operating side of the machine.
The software, which also facilitates integrated job planning, features a drag-and-drop graphic user interface. "For control system software, we rely on the professional skills of experts. We are not software developers - that is why Soflex, the specialist for automation technology control systems, delivers this important component of the system," said Sattelmayer. "This has two crucial advantages: the Production Control Software (PCS) is open and suitable for use by a broad range of machine manufacturers; the customer gets software that functions from the start and is simple to use. Thus, so-called software 'teething problems' rarely occur." NC control of workpiece machining and tool management still function using the usual control system directly at the machining center.
The software is of modular design. Various add-on packages are coupled to the basic package. Liebherr can thus reliably action new applications without special modifications of existing computers. The central customer contact is always Liebherr, which then assumes responsibility for coordination with the software developers.
The Soflex PCS offers:
- The basic version for single-stage production
- Pallet management and status displays
- Priority control for production orders
- Diagnosis tools
- Modular expandability.
For more information contact:
Liebherr Automation Systems Co.
1465 Woodland Drive
Saline, MI 48176-1259
734-429-7225
www.liebherr.us