A torque sensor, torque transducer or torque meter is actually a device for computing and recording the torque on a rotating system, such as an engine, crankshaft, gearbox, transmission, rotor, a bicycle crank or torque transducer. Static torque is fairly easy to measure. Dynamic torque, on the other hand, is not easy to measure, since it generally requires transfer of some impact (electric, hydraulic or magnetic) from the shaft being measured to a static system.
One method to accomplish this would be to condition the shaft or perhaps a member attached to the shaft with a number of permanent magnetic domains. The magnetic characteristics of such domains will vary in accordance with the applied torque, and thus could be measured using non-contact sensors. Such magnetoelastic torque sensors are usually employed for in-vehicle applications on racecars, automobiles, aircraft, and hovercraft.
Commonly, torque sensors or torque transducers use strain gauges put on a rotating shaft or axle. With this particular method, a way to power the strain gauge bridge is important, as well as a means to have the signal through the rotating shaft. This is often accomplished using slip rings, wireless telemetry, or rotary transformers. Newer varieties of torque transducers add conditioning electronics and an A/D converter for the rotating shaft. Stator electronics then browse the digital signals and convert those signals to some high-level analog output signal, including /-10VDC.
A much more recent development is the use of SAW devices attached to the shaft and remotely interrogated. The force on these tiny devices because the shaft flexes could be read remotely and output without resorting to attached electronics on the shaft. The probable first utilization in volume will be in the automotive field as, of May 2009, Schott announced it features a SAW sensor package viable for in vehicle uses.
Another way to triaxial load cell is through twist angle measurement or phase shift measurement, whereby the angle of twist as a result of applied torque is measured by utilizing two angular position sensors and measuring the phase angle between them. This method is utilized in the Allison T56 turboprop engine.
Finally, (as described inside the abstract for all of us Patent 5257535), if the mechanical system involves the right angle gearbox, then your axial reaction force experienced by the inputting shaft/pinion could be related to the torque felt by the output shaft(s). The axial input stress must first be calibrated against the output torque. The input stress may be nanzqz measured via strain gauge measurement of the input pinion bearing housing. The output torque is easily measured employing a static torque meter.
The torque sensor can function just like a mechanical fuse and is an important component to have accurate measurements. However, improper setting up the torque sensor can damage the device permanently, costing time and money. Hence, the torque sensor must be properly installed to make certain better performance and longevity.
The performance and longevity in the compression load cell as well as its reading accuracy will be impacted by the design of the driveline. The shaft becomes unstable in the critical speed in the driveline and causes torsional vibration, which can harm the torque sensor. It really is essential to direct the strain for an exact point for accurate torque measurement. This aspect is normally the weakest reason for the sensor structure. Hence, the torque sensor is purposely created to be one of the weaker components of the driveline.