Definition
An electronic torque meter is a precision instrument used to measure and record rotational moments. It converts torque signals into electrical signals through electronic sensing technology and displays or outputs readable values. This equipment is widely used in situations where it is necessary to quantify the tightening, transmission or working moment of rotating parts.
How it works:
At the heart of the electronic torque meter is a sensor based on the strain principle or magnetoelastic principle. When the sensor is subjected to torque, its internal structure undergoes microdeformation, resulting in a change in the resistance value of the strain gauge attached to it, or a change in the characteristics of the magnetic circuit. This change is converted into a weak voltage signal through the Wheatstone bridge circuit. The signal is then amplified, filtered, and converted to analog-to-digital and is calculated and displayed by the built-in processor to display the corresponding torque value. Torque values are usually expressed in Newton-meters (N·m) or related derivative units.
Measurement method
Common measurement methods are divided into two categories: static measurement and dynamic measurement. Static measurement is suitable for torque detection at constant speed or stationary state, and the instrument is directly connected between the drive and load end for measurement. Dynamic measurement is used to monitor torque during rotation, usually using non-contact signal transmission. When measuring, ensure that the instrument range covers the expected torque range and that the coaxiality of the connected parts is good to reduce measurement errors. The basic calculation formula can be expressed as:
M = F × L
where M is the torque, F is the force, and L is the length of the arm. The actual internal processing of the instrument is based on the calibration curve of the sensor.
Influencing factors
Measurement accuracy is influenced by various factors. Changes in ambient temperature can cause sensor material properties to drift. Coaxiality deviations from the instrument installation can cause additional bending moments that interfere with the measurement results. Friction of the connecting parts, inertia, and fluctuations in the rotational speed of the object being measured can also introduce errors. In addition, interference during signal transmission, long-term stability of the instrument itself, and regular calibration are key factors.
Applications:
Electronic torque meters play a significant role in industrial production and quality inspection. In the field of automobile manufacturing, it is used for torque control in processes such as engine assembly and wheel hub bolt tightening. In electronics assembly, ensure that precision screws are tightened to meet requirements. In the aerospace field, participate in the torque verification of key connectors. In materials research, it can be used to test the mechanical properties of small rotating parts. It is also commonly used in the maintenance of wind turbines in the energy industry, as well as in the testing of general equipment such as pumps, valves, and transmission systems.
Key points of selection
Multiple technical parameters should be considered in the selection. The range should be slightly larger than the daily measurement maximum, with appropriate margins. The accuracy level needs to meet the requirements of specific testing standards. Choose a static or dynamic instrument depending on the measurement scenario and verify that its signal output interface is compatible with your existing data acquisition system. Consider environmental factors such as protection level, operating temperature range. At the same time, the size and weight of the instrument should adapt to the installation space, and the operation interface should be in line with the usage habits of personnel. After-sales service and calibration cycles are also guaranteed for long-term reliable use.