The new digital torque flange for high torques with an improved measuring body design

HBM: The requirements for torque measurement in test benches have kept increasing in recent years. In roller, diesel engine or transmission test benches, for example, ever-higher torques have to be measured extremely accurately.

The measurement technology specialist HBM is putting the T40FM torque flange onto the market. This is a successor to the T10FM series, and can measure torques up to 80 kNm without difficulty.

The torque flange has a revised rotor design and new digital rotor and stator electronics. This combination ensures greater precision and reproducibility in the test benches.

The improved measuring body design results in greater stiffness in all directions. At the same time, it has been possible to reduce the mass, and thus the mass moment of inertia. This improved radial stiffness leads to good bending vibration properties.

The very high torsional stiffness, in conjunction with the low mass moment of inertia, produces a far better natural torsion frequency. During dynamic measurement, this creates the condition for further expansion of the resonance frequency up to higher values. The entire construction is protected, failures are avoided and costs are saved.

The improved rotor of the T40FM has the same dimensions as its predecessor, the T10FM. This ensures downward compatibility and makes it easy to exchange the model in existing applications. Because the torque flange is extremely short, it saves test bench construction space, and thus saves costs. High lateral forces are permitted, allowing the superimposed machine elements to be directly attached.

In the T40FM, measured values are transmitted digitally. A special sigma-delta converter is used for the digitization and transmission of measured values from the rotor to the stator. Digital transmission ensures immunity to noise without loss of data, even in applications where EMC is critical.

Special A/D conversion combined with the high sampling rate of 38,125 measured values/s, safely prevents internal aliasing effects.

The TMC interface in the torque flange stator allows communication with the TIM40 interface module. This supports various fieldbuses, such as CAN, Profibus-DP or EtherCAT. Simple and flexible integration into existing test bench concepts is thus ensured.

More information about the new torque flange can be found at www.hbm.com/en/menu/products/transducers-sensors/torque/t40fm/