Grease-Free Motion Plastics in Klippel Acoustic Measuring Systems

What was needed: The reliable and maintenance-free movement of the measuring robot along the x,- y- and z-axis

Requirements: Lubrication-free and maintenance-free as well as easy-to-install components for long-lasting and failure-free use.

Industry: Stage technology

Success for the customer: The installed drylin linear axes and PRT slewing ring bearings enable the end customer to use the product without maintenance schedules. They prevent downtime and save maintenance costs.

Professionally measuring audio quality can be very time-consuming, as all sound sources are influenced their surroundings. To reduce the environmental effects, acoustic measurements are traditionally carried out in anechoic chambers. However, these chambers are complex and costly to design. For this reason, Klippel GmbH has developed the near-field scanner (NFS).

In the NFS system, a measuring robot scans the sound pressure at numerous points around a sound source in a controlled near-field environment. A microphone is guided around the acoustic source in three axes.

To ensure the reliable movement of the microphone along the axes, the manufacturer looked for suitable bearing technology. When selecting the components, the focus was on both the structure and the handling of the measuring robot after installation with the intent to reduce maintenance work and downtimes to enable flawless and continuous utilization. At the same time, the audio measurement system needed to be grease-free in order to avoid contaminating the measuring devices and test objects. This is the only way to ensure that the complex measuring equipment can be quickly and easily transferred to the customer's own responsibility.

Finally, the systems needed to work flawlessly in fluctuating temperatures and high humidity, which can occur when the product is stored or at the customer's various facilities and production sites.

When developing the near-field scanner, Klippel opted for a PRT slewing ring in the rotary table, which supports and rotates the entire superstructure. The scanner is moved by a drylin E stepper motor with a motorized gearbox. The slewing rings are completely grease-free and low-wear, even at high loads.

drylin® ZLW toothed belt axes are used to horizontally and vertically position the microphone precisely around the sound source. The system includes a drylin® ZLW-1040-S dual-axis unit driven by stepper motors. Operating completely without external lubrication, the axes are virtually maintenance-free, eliminating the need for lubrication schedules and reducing ongoing maintenance costs.

This not only minimizes operating expenses but also helps prevent unplanned downtime, allowing project timelines to be maintained without allocating additional time for maintenance activities. The combination of a strong price-performance ratio and the broad range of available drylin® linear motion solutions was also a key factor in Klippel GmbH's decision.

To ensure the stability and balance of the vertically mounted linear axis, the system was additionally equipped with a drylin® N flat guide and carriage.

Overall, the bearing technology on the three axes enables the microphone to be moved to any point within a cylindrical space.

It is also supplemented by several e-chains, which ensure fast and reliable cable guide on all three axes.