Dynamic Torque Sensors and Static Torque Sensors
Torque sensors are categorised (based on physical form) as dynamic torque sensors (which can rotate continuously through more than 360°) and static torque sensors (which do not rotate continuously).
Dynamic Torque Sensors
Dynamic torque transducers (based on the method of signal transmission) can be subdivided into non-contact torque transducers and carbon brush contact (slip ring) torque transducers.
Non-contact torque transducers do not mean that the transducer does not have to touch the measured body to obtain a measurement. Rather, it refers to the sensor's internal power supply and signal transmission through two sets of coils, the sensor in the rotation will not have friction loss, the advantage of this sensor is that it can continue to rotate at high speeds for a long service life, and at the same time can measure the rotational speed or the angle of rotation, the disadvantage is that the same range volume than the slip ring torque sensors to be larger and heavier (the reason for the internal structure) due to the reasons for the internal structure of the material costs are also higher than the slip ring torque sensors. Because of the internal structure, the cost of materials is also higher than the slip ring torque sensor.
Contact torque sensor we usually call slip ring torque sensor, the structure of this sensor is simpler, the advantages are faster signal transmission, the same range than the non-contact torque sensor volume is smaller, lighter weight, the disadvantage is that it can not be rotated continuously at high speeds, the service life of a shorter.
Static torque sensor
Static torque sensor as the name suggests is to measure the torque in a stationary state, usually the measurement of the motor (rotating body) blocking the turn, static torque sensor and power supply and signal cable is connected together, when the static torque sensor rotates, the cable also follows the rotation, if the rotating body to turn 2-3 laps can be used, as long as the rotation of the cable does not affect the measurement can be, if it is continuously rotating If the rotating body rotates 2-3 times, the cable can be used, as long as the cable does not affect the measurement during the rotation, but if it rotates continuously or rotates for a large number of turns, it will cause the cable to be entangled in the measured rotating body or the sensor to affect the measurement or even affect the operation of the whole measurement system.
