Torque sensor, also known as torque sensor, torque sensor, torque sensor, torque meter, is divided into two categories: dynamic and static, of which dynamic torque sensor can also be called torque sensor, torque speed sensor, non-contact torque sensor, rotary torque sensor, etc. Torque transducers detect torsional torsional moment perception on various rotating or non-rotating mechanical components. Torque transducers convert physical changes in torque into precise electrical signals. Torque sensor can be used in the manufacture of viscometer, electric (pneumatic, hydraulic) torque wrench, it has high precision, fast frequency response, good reliability, long life and other advantages.

How the torque transducer works

Toothed discs are mounted on both sides of the torsion shaft between the drive source and the load. They are equipped with two corresponding magnetoelectric sensors next to them. The structure of the magnetoelectric sensor is shown in the figure. The detection element part of the sensor consists of a permanent magnet, an induction coil and an iron core. The magnetic field lines generated by the permanent magnet intersect with the toothed disk. When the toothed disc rotates, the convex and concave teeth of the disc cause the change of the air gap of the magnetic circuit, so the magnetic flux also changes, and the AC voltage is induced in the coil, and its frequency is numerically equal to the product of the number of teeth and the number of revolutions on the disk. When the torque acts on the torsion shaft, there is a phase difference between the induced voltages U1 and U2 output by the two magnetoelectric sensors. This phase difference is proportional to the torsion angle of the torsion shaft. In this way, the torsion angle caused by torque can be converted into an electrical signal of phase difference.

How to install and use the torque sensor

1. The torque sensor can be installed horizontally or vertically

2. Power equipment, sensors, and load equipment should be installed on a solid foundation to avoid excessive vibration, otherwise data instability may occur, reduce measurement accuracy, and even damage the sensor.

3. It is connected by elastic column pin coupling or rigid coupling.

4. The middle part of the sensor cannot be rigidly fixed, and a flexible connection should be adopted

5. The concentricity of the axis of power equipment, sensors and load equipment should be less than Φ0.03mm.

6. When the sensor is used vertically, the input end and the output end should have a support partition so that the sensor will not be affected by the gravity of the power source and load, and the measurement accuracy has been maintained.

Torque sensor classification: non-contact torque sensor, strain gauge torque sensor, phase difference torque speed sensor

1. Let’s talk about the non-contact torque sensor: its input shaft and output shaft are connected by torsion bars, there are splines on the input shaft, and the output shaft is keyway, when the torsion bar is torsioned by the torsion torque, the relative position of the spline and the keyway is changed, and their relative displacement change is the torsion of the torsion rod. This process causes the magnetic inductance on the spline to change and be converted into a voltage signal through the coil.

2. Strain gauge torque sensor: its principle is to use the elastic shaft, paste the strain gage, composed of a measuring bridge, when the elastic shaft by the action of torque deformation slightly, the resistance value of the bridge will change, and then the electrical signal has changed, to achieve torque measurement.

3. Phase difference torque speed sensor: its principle is to study the magnetoelectric phase difference torque measurement technology, only two sets of gears with the same number of teeth, shape and installation angle are installed at both ends of the elastic shaft, and the proximity sensor is installed on the outside of the gear.

Torque transducer applications

As a precision measuring instrument for measuring various torques, rotational speed and mechanical power, torque sensors are currently mainly used in the detection of rotating power equipment such as motors and engines; Torque and power detection in locomotives, automobiles, aircraft, mining machinery, etc. Whether it is engineering and manufacturing, or transportation, or research institutes, etc., torque sensors are found.