The first wireless RCD with a piezoelectric sensor

Rotating dynamometers (RCD) to measure cutting forces directly on the cutting edge

In machining processes, everything is geared to boosting productivity. A rotating dynamometer (RCD) is a diagnostic tool that is inserted directly into the machine tool's spindle. When an RCD is used, the cutting forces that act on the edge are measured directly on the rotating tool – even when the machining processes are highly complex. The cutting process can be analyzed and optimized with the help of the measured data.

Kistler's RCDs are based on piezoelectric measurement technology. This method achieves superior results as compared to other technologies, with signal quality that is unsurpassed anywhere in the world. The key characteristic: highly dynamic acquisition of the forces. The piezo technology principle makes it possible to switch measuring ranges – and in the RCDs, this advantage comes into full play when users need to select the right range. Just one single device always ensures optimum resolution of finishing processes as well as high-performance cutting processes.

Wireless rotating dynamometers based on piezo technology

Wireless rotating dynamometers with piezo technology can be integrated onto the tool directly with no cables.

Wireless rotating dynamometers (wireless RCDs) with piezo technology open up new possibilities for high-precision measurement and process analysis, especially in combination with new software: the Piezo Tool System (PTS) app.

Thanks to wireless communication, cables in the machine room are now a thing of the past – the receiver box can stream the data directly to a PC. Specifically developed for industrial applications, the PTS app offers all the analysis and measurement functions needed for efficient evaluation of data volumes – no matter how large. Data can also be used for multiple functions: even on small tools, for example, each tooth engagement can be viewed with high resolution, or tool life can be maximized.

Structure of a wireless rotating dynamometer with a sensor based on piezo technology and crystal disks

Wireless rotating dynamometers (RCD) from Kistler are applied for tool monitoring and assessment during machining.

Key features

High resolution for highly dynamic forces
Very accurate measurements of the three orthogonal forces plus torques
High sampling rates of up to 10 kHz
Effective force measurements irrespective of tool length and diameter
Wide force measuring range with only one sensor
Automated analysis software (Piezo Tool System app)

Wireless rotating cutting force dynamometer (RCD) |

Rotating dynamometers with near field telemetry and piezo technology

Dynamometers from Kistler allow for precise measurements of cutting forces – here a polar plot of a milling application.

Drilling and milling with rotating dynamometers (RCD) by Kistler

Piezoelectric dynamometers display their advantages to the full in milling and drilling operations. Thanks to their high rigidity and natural frequencies, these dynamometers cope easily with high tooth passing frequencies to deliver measurement results with a precision level that other technologies cannot achieve.

Optimizing machining technology

Part quality, tool life and machining time depend on different factors. Because rotating dynamometers with cables measure the cutting forces with high precision, they provide the basis needed to assess and optimize all these factors. They include:

wear mechanisms
identification of overload situations
cooling and lubrication
material characteristics
workpiece clamping characteristics
vibrations and oscillations around the machine
no-load operation

The compact model: RCD Type 9170A

The Type 9170A rotating dynamometer (RCD) is the compact member of Kistler's family of rotating systems. Designed for applications in milling and drilling processes, this model was specifically developed for high-precision machining at speeds of up to 20 000 1/min.

Because of its compact structure, the rotating dynamometer with cable is highly rigid – so its natural frequency is also very high. Thanks to these advantages, the Type 9170A achieves the very high resolution needed to measure as many as 600 edge engagements per second.

Kistler offers you an extensive portfolio of standard commercial machine interfaces.

When placing your order, choose the machine interface you need to measure the cutting forces for your type of machining. On the tool side, the ER32 collet chuck is available as standard. Please note that you cannot replace or exchange the adapters of the 9170A due to its integrated design.