HBM (Marlborough, MA) offers the T40B and T40FM torque transducers that include an integrated speed measurement system. They are designed to work in harsh environments such as those that contain humidity, condensation, dust, oil, and grease. The transducers take measurements based on the contactless sensing of an anisotropic magnetoresistive (AMR) sensor, so the transducer signal is more stable than that of an optical system. The transducer integrates both the magnetic technology and the speed measurement sensor.
The T40 features an optional speed measurement sensor that lets the device measure both torque and speed (rpm) at the same time. The transducer measures speed with a 1024 pulse output. Because the radial or axial distance between the sensor and the magnetic ring is 2.5 mm, the rotational speed measuring system has a high tolerance of application-related vibrations. An optional reference pulse signal is generated by a separate sensor that senses the corresponding magnetic field in the axial direction. The system can thus provide the signals to integrate the rotational speed and the angle of rotation in the control loop of downstream equipment such as a data acquisition system.