Precision rotary motion control in measuring system

Headquartered in Germany, Mahr is a global manufacturer of production measuring technology. From the simple caliper gauge to precision optical measuring systems, Mahr is a key supplier in a wide range of industries including the automotive industry, medical technology, aviation, optics and renewable energies. In many sectors where precision is an essential production factor, equipment from Mahr is at work, delivering supreme accuracy in measuring dimensions, contours and surfaces with the smallest possible tolerances.

Mahr received the order to develop a customer-specific system for measuring the roughness of a key engine component for a French car maker. To complete the order, Mahr entered into partnership with Unicum Transmission de Puissance, Nexen's sales and marketing partner in France.

After a preliminary study which they completed jointly, Mahr and Unicum together developed an innovative solution, the only one of its kind in Europe: the Nexen CRD350 rotary indexer. It is capable of very high positioning accuracy during rotation and remarkable dynamic output.

The rotary table is based on a roller-pinion system. It enables both dynamic movements and an exceptional level of positional accuracy. The performance parameters of the rotary table are impressive: Accurate to 35 arc seconds, maximum speed 94rpm, maximum torque 564Nm. Besides these advantages, the Nexen CRD350 is an exceptionally compact drive solution without backlash, requiring no maintenance or lubrication.

Alain Fourcroy, Sales Engineer for Unicum, said: "The rotary table includes the Nexen roller-pinion system with a special ring gear and high-performance cross roller bearings for outstanding load capacity and rigidity. The system is mounted on a cast part. The central passthrough of the annular design allows the essential access to the middle of the table, which is extremely convenient for routing electrical wires or inserting other machine components.

“The application meets the expectations of the end customer in every detail. By combining the expertise of our two companies, we have completed a project unlike any other with complete success."

Jacques Loiseau, Special Developments Manager at Mahr, added: "Demand and need are at above average levels at the moment. For further developments, we want the rotary table to be able to deliver the same accuracy with eccentric loading as well. At the moment, the overhung load is about 250kg with an eccentricity of 200mm. Despite the challenges, we were able to satisfy this requirement with complete success: the ability to handle heavy loads with zero backlash."

Its low structural height and generally compact design make the ring drive system extremely versatile. Apart from this customer-specific development for Mahr, Nexen CRD ring drive systems are used in a wide range of applications including cutting and gantry systems, medical devices, robots, machine tools, semiconductor production, materials handling and aerospace.

Besides ring drive systems, Nexen produces roller pinion, linear and rotary drive systems, industrial brakes, clutches, torque limiters, overload protection devices, and control systems.