Engineers from Droop+Rein are using IO-Link memory modules from Balluff in the milling heads of their gantry machining centers for data storage.

With just one additional cable….

Milling heads with an IO-Link memory chip from Balluff carry their individual characteristic and usage data on-board

Now there are simple solutions that represent great benefits: Engineers from Droop+Rein are using IO-Link memory modules from Balluff in the milling heads of their gantry machining centers for data storage. When a machine is changed or there is plant maintenance, the units always carry their various type information as well as current and historical usage data with them for read-out. The only thing required for reliable and interference-free, bi-directional data transmission between the milling head and the controller is connection of a single standard cable in the system ring of the milling head. Once again IO-Link proves to be a key technology for high-performance, space-saving Industry 4.0 concepts.

Detail of 2-axis milling head

Anyone using Industry 4.0 concepts consistently in practice will sooner or later recognize the inevitability of IO-Link on the process level. This digital interface is a point-to-point connection below the bus level that is internationally certified in accordance with IEC 61131-9 and works across manufacturers independently of fieldbuses. To ensure that the equipment operator is always informed what is happening on the field level and that the controller can work intelligently, current information about the status of the actuators, sensors and tools is always available. The innovative, bi-directional IO-Link interface contributes significantly to making data exchange from and to the process level uncomplicated, transparent and absolutely reliable. Sensors and actuators are linked to the bus or control level through an IO-Link master by means of a simple 3-conductor cable and connector. IO-Link in machine and systems building represents lean, time- and cost-saving concepts – with positive consequences for installation, parameter setting and diagnostics.

The Starrag Group with headquarters in Switzerland is one of the leading manufacturers of precision machine tools for milling, turning, drilling and grinding workpieces made of metal, compound materials and ceramic, employing around 1700 people worldwide. A member of the Starrag Group is Dörries Scharmann Technologie GmbH, known under the name Droop+Rein for large 5-axis gantry machining centers. The Droop+Rein machines from Bielefeld machine workpieces for the aircraft, shipbuilding, automotive and heavy machine industry. Built in kit fashion, these machining centers are custom designed with different machine components, controllers and milling assemblies. The large number of automatically interchangeable milling heads increases the application flexibility, with efficiency and precision playing a large role as always. 

Balluff RFID systems have been used in the Starrag Group for some years for tasks including, but not limited to, tool management or IO-Link solutions from Balluff. To further increase the efficiency, flexibility and ease of maintenance of their equipment, the engineers at Droop+Rein have now fitted the milling heads of the large 5-axis gantry machining centers with a memory medium. “It should be noted that space is at a chronic shortage in milling heads and interfaces. RFID or inductive IO-Link coupling systems are eliminated for one thing out of space considerations, but moreover we had been looking for a technically robust and also cost-effective solution,” says Dietmar Wallenstein, Head of Hard- and Software and Commissioning at Droop+Rein. In close cooperation with sensor and network specialist Balluff the idea of a compact IO-Link data storage medium was developed. The advantage: This IO-Link memory needs only an additional 24-volt control line in the system interface of a milling head to provide bi-directional transmission of all the data. Since the 24V supply voltage is already present in the milling head, the just 34 x 16 x 8 mm memory can be connected directly at the system ring plug, eliminating a separate power supply. Data transmission is noise-immune and resistant to EMC effects, and the installation effort is minimal. 

With an IO-Link memory on-board, every milling head from Droop+Rein will carry with it its individual identification data as well as its relevant operating and maintenance data. Specifically, the IO-Link memory module can hold data of up to 14 segments containing 64 bytes each. 9 out of 14 segments are currently being used: in addition to organizational identifiers such as serial number etc., information about service time, maintenance and lubrication intervals and temperature histograms for the milling head while in use are stored. In addition, information such as the number of tool clamping cycles and excessive shock instances are logged and stored. 

Modern production system for press tools based on two multi-function high-speed machining centers FOGS 50 68 PT M40 C

“Machine operators will profit from the fact that when a milling head is switched from one machine to another, all the identifying and usage data will be automatically copied and loaded from the milling head memory into the NC controller through a cable,” explains Dietmar Wallenstein. For maintenance or service work at the Droop+Rein plant, service personnel can read out all the data from the memory chip from a PC or laptop, evaluate and update it as necessary. This gives the plant operator continual and transparent information about the current status of the milling head. 

Typical for IO-Link, all the data are sent over just a single cable together with an IO-Link master. Use: universal, smart, easy – as the slogan rightly says! As part of intelligent Industry 4.0 concepts IO-Link is a factory automation component that has become indispensable. The mark of a “Smart Factory” is that the central and decentralized control units have information about the status of the actuators, sensors and tools, that data carriers attached to the workpiece tell the system which process step should come next, and that the plant operator knows always and from any location how production progress stands. “With the cost-effective IO-Link memory chip on-board the milling heads our customers benefit from the resulting reliability and productivity. We as machine builders profit from increased transparency about the use and utilization of the milling heads on our machines,” summarizes Dietmar Wallenstein. An added-value solution that in this or similar configurations will doubtless find application in other machines of the Starrag-Group. 

Source: Balluff

Author: Wolfgang Zosel, freelance industry journalist in Reutlingen